I agree 1000% with all of these points, except 2) and 3) :
2) Just at the starting point of the jump.
3) Attack of opportunity should always work. Armor Class is already here to decide if u can or not avoid this attack. But we could imagine a Disengage action (different of jump) with an accrobatics/athletics test.

Last edited by Tylm; 14/10/20 12:32 AM.