I played a Roman vs Carthage custom 1v1 battle with huge units, 10K denari and a 20% reduction in movement speeds. This put a total of about 5000 men in the battle. The major fighting lasted about 10 minutes, and each side got about 1500 kills. I spent an additional 10 minutes chasing remnants, and exhausion did slow down that process. The movement animations looked fine except for some noticable slipping on walking infantry at times. I didn't notice any lag, but I never had all the units in my field of view at once. For some reason the camera was restricted to the general's view, even though I had selected unlimited camera in the options. I'm going to try more battles with huge units and the 20% speed reduction. BTW, there is no tax for more than 4 of one unit type, and upgrades are very limited at 10k denari as are the better unit types. You can't just load up on all the best units at 10k by a long shot.