What are the various types of tavern patrons, and what are the differences between them? The wiki doesn't say much about them at all. Furthermore, how does permanent residence work with the patrons?
I don't like being that wiener
weiner. But, there have been a number of topics on this. Searching "residents" or "patrons" gives lots of results.
To answer your question though:
Depends on what you mean by patrons I guess. People just coming to your tavern? Come in all varieties. It is mostly soldiers, performers, scholars and the occasional noble. I've seen a pretty wide variety.
The two big permanent residents are entertainers and mercenaries. You can get troupes of performers who can petition to stay in your fortress. People have mentioned monster hunters, I haven't had any, personally. You cannot assign labours to residents. Entertainers will generally hang out in your tavern and interact with your dwarves. They perform too, often with their own instruments. Mercenaries can be added to squads but cannot lead them.
I've found that the number of visitors you get jumps up at specific points in play. You'll only get about 3-4 visitors at a time when you first open your doors. When you hit about 50 pop, you might get a bit more. As soon as you have a mayor, you'll get a flood of people. It will seem to just never stop. People coming and going constantly.