So I played around a bit and found some improvements.
1. I was able to save 4 frames on the first level by jumping differently. by landing on a downward slope, I was able to minimize Chester's bounce to only last about 2 frames, then lowering my bounce time on the last crab. jumping on it is required to get that map.
http://tasvideos.org/userfiles/info/46833070186894443
2. second level you can release the run button mid-air to prevent Chester from skidding before he jumps. saved about 3 frames.
http://tasvideos.org/userfiles/info/46833079500019581
3. in unclear water, you can do a short bounce on the last gator, then one on the snake, and finish the level faster since you dont have to halt when you land. even though Chester's victory animation doesnt play until he hits the ground, the level will still end as if it did end. 14 frames saved.
http://tasvideos.org/userfiles/info/46833085397366458
every one of these movies desyncs after the level is completed by the way.
that was as far as I was willing to look through. I really do like what you've done so far and I hope these improvements can help.