Though as craptacular as Dispel is, I think it would actually be useful if:
(A) It worked reliably
It does work reliably though. It isn't affected by the solo multiplier and additionally a 70% hit rate is pretty good.
(B) It pierced reflect
I agree with that.
(C) More monsters started with statuses worth dispelling
It's actual prime use is to remove Berserk and Reflect, but the problem with that is..
Berserk - There's no reason to dispel your own that have Berserk status, plus the monsters that actually cast it are like two tree monsters.
Reflect - The only monster worth using against is the EvilMask.. the problem is that the monster has the boss bit and the spell has it too, so it always fails.
I don't have a list of monsters that cast reflect, but I think the IceKnight (Ghost Knight) casts it as a counter... Baigan does.. and just the EvilMask. Otherwise, I can't really think of any major monsters other than a few more in FF4A that use it.
Not many other monsters take advantage of other statuses anyways..
Status Effect: removes Berserk, Stop (only when Count/Doom is inflicted),
HP Leak, Wall/Reflect, Barrier, Image (2), Image (1)
Making it a more offensive spell seems to be the way to go IMO.