A:EMH is getting a 52 episode order right off the bat, so that will not only ensure two seasons, it will ensure that it gets as many episodes to air as "X-MEN EVOLUTION" did, which was the last Marvel show that lasted 52 episodes. I think before we worry about a third season, we at least hope that the fact that this is the first Marvel show that will last 52 episodes since Bush Jr. was running for re-election isn't lost on some fans, and that the production team fully capitalizes.
If A:EMH got a third season of an additional 26 episodes, though, it would reach 78 episodes and the episode count of the 1990's X-MEN, which stands at 76 circa 1993-1998, would finally be broken in Marvel Animation history. But that's in the future. Assuming another season would come that never did doomed a bit of W&TXM. This show can't muddle around and hope to fix things in season 3. It has to kick *** now. And at least from the trailer, I do genuinely believe it's going to try. The Avengers deserve no less.