Chemist has been discussed quite a bit by the community for wanting it to be the next healer, unfortunately for the people who want chemist (me) dancer is picking up more hype and seems to be the obvious choice for the next healer which honestly won't be bad because it could give us a melee healer which sounds interesting.

A post was made a while back with what you seem to be getting at with the whole ninja mechanic and it really sounds fun and engaging.

Link to that post: http://forum.square-enix.com/ffxiv/f...threads/344022