First of all, goodluck with the game G.P.G.! As an avid DOTA-gamer and Gas Powered-fan, I look forward to this first retailgame entry in the young strategy/rpg genre.
Here's my two cents. When looking at the screenshots, I notice the playing fields are very open. There's no fog of war. There are no places to hide. There are no alternative paths to take. This means you are either going for a hack 'n slash direct confrontation or you are still developing the arena concept. I really hope it's the latter. I know this isn't the same game as DOTA (just inspired by), but one of the things that makes that game so fun and challenging for (pro) teamplayers, is the tactics the environment offers. Hiding for a moment out of the line-of-sight to surprise lone Demigods. Using smart pathing through the trees to escape an ambush by a group of enemies. Or simply retreating into the fog-of-war to unexpectedly switch sides with a more effective teammate. These are all tactics that greatly enhanced the concept of multi-player team-rpg's. If you take that out, all that remains is pure combat (the biggest guy always wins) and no interesting team tactic. It's also one of that factors that prevented the imbalance that plagued related games as Footmen Frenzy/Wars. (btw, I read a reaction on this forum that Footmen was more balanced that Dota. I strongly disagree. With good teamwork and tactics a losing team can always make a comeback in Dota, while with Footmen some people get overpowered too quickly and the game is lost). Demigod balancing, item balancing, level balancing, structure balancing, footsoldier balancing, etc are all very important. But what makes a game a teamgame is the tactics they can use. So I really would like to hear what Gas Powered Games has to say about their environments and how they expect teams to play.