How about a midair jump? Like, you fall off of a platform and you can do another jump, that would help the Assassin's midair mobility without having to use those slow smoke bombs.
No. The Assassin has enough mobility right now. I say we fix the issues she has, then talk about new skills.
Nah it's not necessary. Smoke bomb is more than enough, and it's not too slow...you just have to know when and how to use it effectively.
Double Jumping Assassin would be REALLY REALLY REALLY REALLY awesome. It'd make her so much more fun. But like JON said... fix her many problems and THEN worry about new things.