Well I love the theory unfortunately reality is not that simple. There are some maths to do to convert the anims into something usable by the game. Being able to select each bone in Atlas, move them and then record the motion is not going to be easy, let apart the fact of it looking cool. There are only two volunteer and highly talented artist that work for the game currently and that are able to add new stuff to the game. But if you want an animation editor into Atlas, you can make a ticket on Trac, wait until someone does it or find someone to do it. Trompetin17 is currently reworking Atlas, you might want to drop by on Irc and ask him for his input on that.