Some after-battle-ctd's are triggered by closing too fast the 'battle result-tab'. Especially when the fighting involved numerous soldiers, your pc needs some time to calculate everything towards the campaign map: give it some time. Waiting ten seconds after a battle usually does the trick. If that wasn't the reason why you experienced your ctd, then the AI hating your blatant victories is. :) Besides: you did set autosave on 'each turn', right?

About different factions: go ahead and experience some more pyrrhic victories. You may also want to increase difficulty levels.