Seems a lot better than trying to build in admin orb mode. You should release this
Some random thoughts:
Should be enabled by pressing space twice instead of a custom key
Should keep your aim exactly (both left/right and up/down) when you toggle it
Shift to go down, space to go up?
Right click is no longer wasted for jet, use it for something useful?
Works with third person mode?
Works with dup?
Can it be done without a client mod?