In the four thousand years since Christian Civilization began, the economy of the vast majority of Kassidor has changed remarkably little. It is a civilization richer in man-years than all others in the Empire combined. Most of the founders of this civilization are still alive, it numbered only a few dozen million when the Kassikan first marketed a working cure for ephemerality in humans.
In 4100ad the vast majority of the planet's forty something billion people still live off their land and take odd jobs for spending money. When they travel they invest years and work their way at odd jobs. The planet is as 'poor', per capita, in money as any in the Empire including Earth and Kinunde. The distribution of wealth is as skewed as any with almost everyone having nothing but their home, a patch of ground and a few coins left from the last time they went to market with some crops if they're 'rural' or took a day job if they're 'urban'. To buy a house and land, they must work long and hard and/or sell their old one.
The devices and conveniences they have afforded have changed little in four thousand years. More than half of all showers are still outdoors. There are power services only in the densest urban areas and it is delivered as compressed air, gas, or sugar water. Most of the planet's residents cook with wood fires, usually deadwood they picked up themselves. Most people live most of their lives outside the money economy. To many of Centorin, especially the marketing lobby, this alone seems like grounds for a military invasion, but the Kassikan is the keeper of the portal to this world and guards the people's right to live outside the money economy.
The biggest change since contact has been the ability to manufacture photo-electronic devices and that has changed the cost (but not the speed) of data communication to the level that the masses can afford it. For a few years it looked like the planet would go the way of Earth at the time or Centorin today with universal communication, but that fad lasted little more than a standard generation. Between the Angel contact and the rise of Centorin, Kassidor remained as the most technically advanced human civilization in all fields. When the early Centorin civilization contacted the Kassikan in the 3200's it was Centorin science that learned, even in energy physics.
The biggest change since the stargate has been the advent of metals in enough quantity to make long-range tubes possible, and the growth in that system promises to consume almost all the metal imported for the foreseeable future. In 4100, five sixths of the basins (by area) are still inaccessible by tube.
The price of long range transportation remains out of reach of all but the affluent or determined, the bulk of the people still travel outside the cities by foot, sail and cart, and inside the cities by foot or animal-drawn cart.
This does not mean that the residents don't enjoy a high level of comfort. Agriculture has been perfected to the point where starvation is not an issue for any significant population, isolated waterholes and lost travelers account for about all of the innocent ones. Most who starve do so because they are so deep into some drug they don't bother to eat.
Homes take longer to grow than an ephemeral human can live, but most are already grown and have been for centuries. An archwood home can potentially live ten thousand Earth years. There are very few without access to a pleasing shower at least once a week. They have far fewer possessions than most Empire citizens, a few changes of clothes, a place setting or two of tableware, a half-dozen cooking pots at most, a half-dozen utensils at most. Their few possessions are often of the highest quality in the Empire however, many are unobtainable anywhere else. At least a million shower heaters built before the renaissance on Earth are still operable, most are still in daily use. A fine commercial cooking cauldron can cost as much as a small home but can be expected to be in service longer than any stargate has so far.
The labor it takes to maintain this lifestyle is about one day out of the week. The garden may be more pleasant to work in Morningday or Afternoonday in one part of the year or another, or in one part of the planet or another. Nearly a quarter of the planet's population will experience frost almost every week, but almost none will see a week that doesn't reach 60F (16C). There are few other than a few Mountain Trolls who endure frost during any significant fraction of daylight hours any time during the week or year. All who live in the thick air do not understand the possibility of frost except as an intellectual exercise and in ancient times whole civilizations rose and fell that did not know ice was allowed by the laws of physics.
The urban poor must spend at least one day of every week at a job and often two if they want to save up for something like a house. Once they have some skill they can eat drink and be merry on one day a week, begin to accumulate a fortune on two. It is almost unknown in the current culture to work three days a week, even among the most driven in the most affluent towns. Even in ancient times the poorest peasants only worked two, the better off peasants also got to socialize on Nightday.
There are very few without access to some social and cultural interaction and those in the cities have always had the most access to cultural stimulation of any people in the Empire and in most areas continue to do so today. The heavily censored sample of Kassidorian video and music we have access to in the Empire is the cheap stuff available to the urban poor in some quantity. More of Kassidor's economy goes to arts and entertainment than any other planet in the Empire. Though one thousandth as wealthy as Centorin numerically, it's arts and entertainment economy is actually larger than Centorin's because such a large part of the vast population participates. A musician might earn between forty and four hundred credits a year, but there are as many as a billion of them. While Kassidor has a billion musicians, the remaining Empire had nowhere near a billion people observe a live performance in 4099.
But the most skewed statistic in the lifestyles is probably this. There were 207 million people in the Empire outside Kassidor in 4099 who ate a commercial, human-cooked meal. There on the order of two BILLION people on the planet Kassidor who will cook professionally this week, earning an average of 400 credits per Earth year. A billion people will sell some form of entertainment in some media this year, another quarter trillion credit section of the economy.
From the starving post-photographic sculptor to the trillionaire founder of a media empire, entertainment and media is the major component of the money economy. People have a lot of time on their hands, they use a lot of it entertaining each other. A planet with it's population and energy resources can't really have a lot of people entertaining themselves with high energy vehicles for instance.
The rich of Kassidor are different from most of the empire in that they have little direct power over people. They may run large organizations. The organizations are voluntary and everyone understands this. A manager seldom assigns projects to subordinates, he offers them and the subordinates would choose their projects. A manager would always ask a new signee what hours they would like if it was something that required filling a schedule.
But the rich of Kassidor are very rich. They have often had more time to amass their fortune than we can imagine. Most of the current rich have been building their fortunes since before Scrooge went about it the wrong way with the ghosts of Christmas. A few of Kassidor's rich have been building their fortune since before Midas. They may own vast industries. They may live in great castles on pinnacles of country or city. They may own great ships of the rivers and canals. They may have a staff of thousands just to care for one palace. Their opinions matter more than others, they can set the public taste, often in ways they wished they didn't.
The rich have enormous expenses to safeguard their wealth. The Instinct has made violence impossible, but not thievery, and so much wealth can be coveted. Their homes are often fortresses, and may have the look of fairy castles in some cities but the weapons they are protecting against are crowbars and grappling hooks.
Before the time of the Angel civilization, the rich enjoyed data communication that the poor did not, since then, most can afford it. The rich enjoy motorized watercraft and a bioengineered lighter-than-air plants called floaters that make air travel possible. In the modern world those in the nearer basins enjoy long distance tube travel (though primitive by Empire standards), interstellar travel and motorized sport vehicles. As a class the rich make up a tiny fraction of the population, with no more than a few million rich enough to be considered rich by Empire standards.
There is little distinction between the poor and middle class. Practically anyone who wants to accumulate a little wealth, a nice home or spread, a few employees or servants, can do so. Anyone capable of learning a marketable urban skill can do the same. There is a remarkable amount of fluidity between the classes and many individuals spend time in each, 'trying it out,' you could say. There are some who may lack the intelligence to make the middle class but if they can exert themselves, they can purchase that intelligence without a significant skill.
The affluent in Kassidor Yakhan earn about the equivalent of 1200 credits per year at current exchange rates. It is unobtainable via unskilled labor, but common among professionals. With this one may employ a live-in cook/ housecleaner, own a whole room full of genuine paper books, some of them dating back well before the bible was first hand-written on Earth, and be considered an important person by customers, suppliers and employees. One would own about two thousand square feet of indoor space, furnished as comfortably as the home of a Centorin professional. There are few private tube stations and this would not allow you to have one, but it may allow you to live in a building with an elevator.
Despite the mobility and the low point of entry, the middle class is also tiny, less than 10% of the population, four billion at most. But yes, in absolute numbers that is the largest of any planet in the Empire. It is still almost half the middle-class population of the Empire in 4100.
In absolute numbers Kassidor's economy was only the fifth largest in the Empire in 4099, but if all the food grown and intoxicants eaten, drank and smoked by its people were counted in the money economy, it would easily leap past Earth, Kinunde and Naiho to rival Centorin itself.
Because of it's slow growth and stagnant culture, Kassidor will undoubtably become less important overall as a part of the Empire than it is today economically, but as more of it is connected to the tube system and it's vast size and diversity becomes more appreciated, it will remain an important planet for the foreseeable future.