The problem is Toriyama isn't a game designer, he's an event planner. It means his strengths are in story and scenario. The reason his games have 'excellent' battle systems is the involvement of game design underlings. There's no talent from Toriyama in that department.
Just to play a little Toriyama's advocate here.
Toriyama is like weird extract. He's too potent to put in large doses, and you shouldn't make an entire dish out of him, but he can really add a lot of charm to something other people are making with him.
Namely the Wall Market section of FF7. What an insane, yet awesome section. DON'T give me an entire game like that, but DO put in sections like that to surprise me!
Toriyama's strength is shaking things up, but his weakness is when he is left unchecked, his creations have a tendency to be too out there for people to like.