I gave up in the first level that you get two time leaps. I did so when my second ghost didn't behave like I did in my previous playthrough: it was supposed to wait to the right of the first ghost and then jump on it, but instead waited its left and jumped at nothing.
The fact that you can push ghosts is very annoying. That's what I guess happened in what I just described, since everyone starts in the same spot. Maybe the second ghost started walking straight away, and I ended up pushing it a little bit to the left. But either way, I really didn't like the fact that I had to be careful with that.
The timing for jumping on a ghost is tough. I didn't mind in the levels I played since they were short, but on longer levels with more time leaps, I'm guessing I'd be frustrated.
The acceleration-based air movement feels a little bit weird, wouldn't be better if it were constant speed, like mega-man? Unless you had ideas on how to exploit that kind of movement.
A few ideas I have to make it easier on the player would be to make the ghosts untouchable (and you'd jump 'in' them, not only above them), or just make it so that the player can be pushed around by ghosts but not backwards.
I had fun with it, though, I think it could be really fun! I enjoyed playing that one level that was all vertical, and I bet there are all sorts of fun things you can plan with the time loop mechanic, so keep at it dude!