WAG Floor skills grading

[twistingmia]

I am not at a very high level yet and have a question about tumbling skills.
I will list all of the skills I am familiar with and will sort in from diffiiculty low to high!

Forward tumbling skills:
Front walkover
Front handspring
Flyspring
Front Tuck
Front Pike
Front Layout
(is there a "front whip??")

Backward tumbling skills:
Back walkover
Back Handspring
Back Handspring Stepout
Back Tuck
Back Pike
Back Whip
Back Layout
Back Layout Step Out

I know there are twists and double flips as well, but I don't want to cover this now.

Did I forget anything?

Is a pike, whip or layout a lot harder than a tuck?

Is it a lot easier to do those things on a trampoline than on an airtrack? Of course, if you can do them without much momentum!
I have most of them on my trampoline at home and would like to try some on the airtrack!

Hop someone can help me