Most FF battle systems are shallow. XIII's problem is that there is little exploration, shit pacing (symptom of no towns) , and that the tutorial lasts 25 hours. I highly doubt Type 0 is that bad.
Type 0 has little exploration (there's a world map but there's little to explore, shit pacing (almost no towns, every "town" is just a copy & paste of a single town and there's nothing you can do in towns besides talk to NPCs standing around (think of FFXIII's towns), but yeah the game gets going right away.
Battle system is waaaaaaaaaaaaaaaaaay worse than FFXIII and it's super low budget with tons of copy & paste everywhere + shitty 30 min RTS battles that FFXIII didn't have.
Both games are equally mediocre, just in different ways. They both have some really good stuff, but a lot of bad design choices as well, so they're both pretty meh in the end.
so what's the battle system like then? And why is it shallow.
You wait for the enemy to attack, hit dodge, then hit O to counter instant kill. The end. Repeat for 30 hours.
Think Assassin's Creed battle system.