I think the next thing Valve needs to do, after making this mysterious new game mode, is a new Medic update of some kind. If you compare the Medic of today to the Medic of the release, he's almost the same. Sure, he has access to the Kritzkrieg, but that's it.
No wonder people get bored playing the medic, it's been the same thing for over two years now.
I also find it frustrating because it's so reliant on others' abilities. If your team is bad at fragging, the best healing in the world isn't going to win the game.