Somewhat linked to my other thread around ideology axes, I had a few reflections on how gameplay around Independent Peoples could be improved.

First off, some simple user interface suggestions:

1. It would be useful to add a tool-tip or some tutorial that bribe and praise cost goes up by era. At least that's my impression.
2. It would be nice to have a panel of all IPs to keep track of who is around. Similar to the cities panel.
3. It would be handy to show in the diplomacy window whether a major faction has client states and, if so, which ones.

But also a few gameplay ideas:

1. Liberated cities and outposts should get patronage depending on the original cities stability. For a settled city over 90%, I think a liberated city should move straight to client state status. A low-stability (i.e. unhappy) one could move to the current state of just 10 patronage and no pre-existing relationship. That would nicely simulate the terms upon which the cities were released and whether it was more voluntary or forced. This could simulate some of the nice gameplay with vassal cities in AoW III.
2. Similar to the above, liberated cities and outposts should inherit the origin culture's ideology axis positions, possibly dependent on the stability value of the origin city. It makes little sense to have a liberated happy city have a totally different position.
3. As a consequence of those two changes, maybe the city limit penalty could be increased, for instance made into a direct stability penalty as in the Vanilla Improvement Project mod? In that case, the major factions could still go beyond the city cap but have a viable alternative to temporarily manage the penalties, with an option to assimilate again later.
4. Allow sufficiently unhappy cities to outright declare independence. At least, I don't think that's possible yet, is it? The most that happens is that IP military units are spawned which may or may not succeed in conquering the city. But it cannot revolt straight to IP status.
5. Finally, a big-bang idea - enable IPs to become major factions. If successful enough after a while, they may get offered a choice of culture. An example of this is a mod for Civ IV (https://forums.civfanatics.com/threads/py-modcomp-barbarianciv-barbarian-cities-settle-down-into-full-civs.170243/) and I found it to add some really nice dynamics to the game play. Essentially, you naturally had a diversity of more and less advanced factions and kind of buffer/client states. In many ways, the much more common "minor civilization" mechanics in many games since then picked up but also obsoleted the concept. And I don't really expect it to be realised. But it's a cool idea and could throw some dynamics into the game.
6. Edit: one more. Scale the benefit of the money treaty better with era/over time. The science treaty scales alright (though maybe could use a bit more tweaking on the extremes?) but the money gains are pretty paltry. I saw 18 money in the classic age just after a IP founded its city and just twice that in early modern. By contrast, science went from around 30 to around 120.