Hey, I noticed the slow and unresponsive attacking in the build version, but only had a couple of minutes before submission was due, so sadly I couldn't fix it in time.
Coyote time is a good idea man! Didn't even think of adding it, but it probably should be implemented in every kind of platformer :D You're right, camera shake would definitely be a nice addition, along with other particle effects, maybe even post processing :)
Thanks a lot for your feedback! :)