At the risk of hijacking this thread, there are a few things I can think that vastly improve the game (at least for me):
#1 Massively reduce rebel spawns. It is no fun fighting 10 battles a turn vs rebels, and while in the midst of running the Roman Empire, to fight a battle when 2 units of Rorarri rebel next to a full stack of Legionaries. Much more fun to focus on the fights between yourself and the AI, full stack vs full stack, with results that actually mean something.
#2 Put an extra 10k per turn into the script for the AI and play on Medium instead of VH for the campaigns. You can actually make and keep treaties, and are not at war indefinitely with opponents. Also you don't just face armies of Mercs.
I know some people use the Force diplo mod, but that takes away from the randomness of the game for me.
#3 Give the AI governor's structure 100 to happiness, to prevent the problematic rebellion bug.
I've done all these (and much more) to my files, and the game is so much more fun.
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