Also, anything that reduces the number of units to be moved in the game would speed up things enormously!
I very seldom finish a game, because I find the repetitiveness of moving hundreds of units in the modern age so boring...
Reduce a stack of 10 Infantries in a city by bombarding with 50 Artillery and then attacking with 12 Cavalry...rinse and repeat.. *yawn*
Turns taking an hour at a time to just move your units... I ask you! That's work, not fun!
One option would be to simply reduce the number of units available overall, for instance by making # of units dependent on population (saw that on the consolidation thread). Or dependable on available resources (saw that somewhere as well).
Another would be improved stack commands - e.g. tell your stack of Artillery to bombard till all defenders are redlined then stop - dto. all your Cavalry in the stack / only those with full hit points attack till city falls.
The stack command should resolve automatically with immediate results, no waiting for 50 individual artillery barrages.
Actually, I'd prefer a combination of both options: fewer units AND improved stack commands.