Best places for type 3 and 4 govs and other stuff

As the title says, what are some of the best spots to install a type 3/4 gov? I've always figured Massila would be a good locale as it has both regional celtic and hellenic troops but I am curious about other spots. Any other good places that give either a unique unit or a nice medley? This of course assumes you are an invader and my current expereince is with Carthage and Rome so essentially I've experienced most of the western half of the map and only Massila has really stood out. I may be missing something there though, and it'd be interesting to hear what are some prime eastern turfs.
Also, is there any way to make an AI faction accept peace with you after you have severely whooped them? In my Carthage campaign I've pushed the Romans completely out of Italy, originally leaving them with only Segestica. I have tried several times to get peace, even going so far as to offer to pay them money, but they keep saying that the offer can't be matched and thus they must refuse. While they are harmless to me now, they have begun to expand again and I was hoping that a few new territories would soften their mood. Still no luck. Any way to get them to be at peace with me? I like them as a convenient buffer state to Sweboz and Epeirotic expansion and would rather be at peace than swatting away the occasional attack by them :smash:.

The area immediately around the black sea is pretty good for Galatians and some HA.

Depending on who you play, try out places like Helvetis, Krete, Galatia, Syria/Assyrie, etc for unique units. For places with many regionals, try places where two cutures mix, such as Babylonia, Massalia, Bosphoria, etc.