depth perception is a problem in water combat. I can't see it being any different in air. just wonder how casting while moving would be handled. I mean what is the point of flying if you have to stop and hover to cast? just a thought.
Aion's big problem was the realistic take on flight. It took energy, and when you ran out, you fell to your death. :\ I dunno about you, but I don't play fantasy games to have realistic annoyances. >.> (The character creation details were AMAZING though!!! I miss my orangutang looking dwarf thing.) The other huge problem I remember about Aion was open world PVP... and the PVPers would just hang around the entrance to the zone or the respawn spots and repeatedly gank the unfortunate souls. :\ I quit the game when all that was left to do was in the section where it was all open PVP.
Yeah Aion was a nice bait and switch for PVE players, was nice up until like level 40 then it was jsut grind quests, mobs or pvp. bleh