Ha Ha...I go the exact opposite on the men's vaults. I don't like the straight jump and love the front tuck.
If a straight jump is done powerful and tight, it will rotate forward causing the gymnast to land on their face. The gymnast has to pop the belly forward a bit to maintain the upright position.
I love the tuck for the pure power that you can put into it. You are right about the heel drive. I think of it as a drill...the heel drive is not what's being taught in this drill. It's the approach.
I don't teach an arm circle on floor...but I have seen some gyms that do.

I'll start a thread on this one.