Originally Posted by Dr Unne
FIR2, LIT2 and ICE2 can make a difference, if only to mop up what's left after your RM/BM is done. FAST can obviously make a difference. Every turn in battle matters. You can save a turn worth of waiting for your RM/BM to cast FAST on you, by casting it on yourself.
Ninjas are the second best in the game in terms of the quantity and quality of types of armor they can wear. I believe they're the first best in terms of how many weapons they can use. They are the only class which can use the third best weapon in the game.
They do seem to run better, in the remakes if not in the original. I don't know if the game mechanics back that up, but it seems so at a glance.
Everything is useless compared to a Knight, yes. Sometimes it's fun to take a party that's a bit weaker with greater variety. There's more to the game than maxing your stats. Armor and weapon discovery in the dungeons is lots of fun for me. But only if you actually get to use it all. Getting new magic is lots of fun for me. Ninjas are fun.