IMO they miscalculated. I am sure at least we could reach level 6 in AE. So a final level cap around level 10 would be to low (if there are more then act I). So they have to give you less XP during the begining hence they have to cancel some enemies cause you are not as powerful as now. Of course later you won't level up as fast as now but they they have to make sure that you do not reach the final level cap way before the end. So either they increase the final level cap up to 15 (maybe 20) or they decrease the amount of XP during act 1. But playing without level up is boring.
