The game doesn't tell you how your incoming forces are arranged and what the support cost of them is, so figuring out the number of your support bottleneck isn't easy.
If you want to auto-resolve everything, that's your prerogative. It would be a neat feature if Dragon Commander 2 let you choose which units to deploy yourself (it's too big a feature to expect it implemented in DC 1), but the support cap and army truncation has to stay.
If you were to remove the support cap, and deploy as many units as you have, then the political decision making would have absolutely no gameplay effect at all. It's not supposed to be easy to win a war if the population of the country you're in hates your guts.
