I prefer AAS actually, I think it gives more reason to play logi and set up FOBs (You can actually build FOBs on both teams huzzah!) and maybe the biggest thing is that in AAS if your squads aren't talking to eachother you're fucked. Coordinating which squads are attacking the next point and defending the current one, setting up "leap frog" maneuvers to take subsequent objectives etc. is just more interesting to me especially as squad lead, when in the other game mode everyone can just file into the one or two points and not really need to communicate at all to secure victory. I really like the ability to counter attack the enemy and re take objectives after you've busted up their assault.
However, I will contend that with low population count and/or with a "bad" group of pubber SLs AAS can be a miserable hellscape programmed into your computer, with things like the lack of a logi squad to build FOBs and the lack of MSPs becoming maddening after about the 5th time you've had to drive (or walk, if some asshole has just been using the transport vehicles as a one taxi) from main after a death.