[TheSlyMoogle]

Uhm 6 is really the only game that doesn't fit the pattern. 1,3 and 5 do have terrible stories. 5 is the worst offender in my opinion considering the time of its creation. It's pretty obvious in that game the just focused basically on the battle system. Honestly the guy probably wrote the game script in like a night while drinking copious amounts of Saki.

2 and 4 are basically just a story. You can honestly go through both just mashing buttons if you fight enough random battles.

6 is the only one with something different to offer, however... 90% of the bosses and enemies in the game can be defeated with the vanish/doom technique and there's another technique that can be used on those who can't. So I think 6 can go either way. Yeah you can make it complex, or you can just go with it.