My opinion stands that wars have to be more fun. Two weeks, maybe 4 max. Any longer and the loser should lose, but turnaround mechanics post blitz should exist.
Damage is the obvious change, but not on nukes. Maybe perks or projects that could just give flat out more damage, no reduction.
To counteract, peacetime profits could be buffed a little, but there should be like some penalty to staying at peace. So if like a sphere decides to sit and whale indefinitely, they'll be at a disadvantage.
I like the total wars requirement for projects and project slots. I'm also fond of the idea of a project that lowers pop but makes rebuild cheaper.