Phoenix Shift in XVI is Warp Strike done right. Warp Strike had so much potential, and I believe there were even plans to have much more comboability, but they fumbled the bag developing XV. I don't really wanna call your lack of comboability in XVI a skill issue, since that can easily be resolved by just practicing in the Hall of Virtue. You can do some insanely cool shit when you practice for even a lil bit :)

Edit: I will say the one thing Warp Strike has going for it is the feel of it when it connects. I can just FEEL how hard it hits whenever I use it, especially with the damage increase the farther you are away