In CMs deadeye(or reaper) for power, specter for condi, specter for alac and for T4 i go either daredevil either deadeye. Swapping is a template click just no harm. If i am stuck on HFB role then i dont roll.
In sum: power deadeye is insane good for single target T4 fracs and daredevil amazing for the aoe T4 fractals. so you can have 2 templates and do everything
dont stay on the top, stay a bit more down and care to not hit your head on the rock roof so put your legs to "fly" a bit. The final vault part should be not in the same ground level with your feet, must be higher or lower (any works for me). Also make a mini jump the moment you touch the ground, this is the main trick, and works like 2/3 times mostly cause is hard to estimate the vault height.
well i just tried, just focus making that mini-jump after the vault thats all, i time the space exactly the moment the vault touches the ground to interrupt the falling animation.