It should be noted that everyone has the same priority guard so Heel Crush and Fusillade act the same on everyone. The difference is that some people have moves that can block them (Ultimecia, ExDeath etc.)
EDIT: That's not quite how I meant it. Some people have moves with the block priority high enough to block them. Pretty much everyone has moves that can go through them.
If anything I would much rely on fated circle, mystic flurry, and revolver drive with assist or EX revenge Squall is a short distance fighter I much rely on fated circle because it closes in before it attacks anthing from a distace I would rely on blasting zone, rough divide, or heel crush for closing in.