Something i ran into alot while playing DOTA, was that It felt unbalanced at the beginings alot. For instance, if you were a melee hero and the other guy coming down the same path as you on the enemy team was a mage youd git peppered with spells while trying to lvl up, which really put a damper on things. Now granted "Pros" may not have had these kinds of problems but i was never a pro and while i really enjoyed the game play of DOTA style i could never get into it because certain people you just couldnt fight. Or they knew the best heros blah blah.
I guess what i'm saying is that i'd really like there to be a good balanced way for every type to level up. Keep the playing field leveled, course i would help to play the beta to

totally looking forward to getting some idea of how the game is really gonna be.
Also, it seems like there is essentially two "classes" General and Assassin, If we are considering the assassin as a "Hero" type, lone wolf so to speak. Will there be different types? Like my idea of a bad ass hero, is a guy who can drop turrets and be an area controller, Guns are cool right? Hehe ok fine but when i think demigods i immiediatly think Hercules or michael. It would be cool if this game had destructible terrain or impacted terrain, so if people unleash awesome abilitys (which i think they should be able to do) It would deform the terrain. Or ya know bringing down one of those big dudes would make impacts and such. Basically i would like to see stuff affecting stuff.
Epicness, cause right off the bat those colossus guys reminded me of shadow of the colossus, and ya Animations. Please dont have redundant animations on heros and such.