With the exception of FF4, 9, and to lesser extent, 6 and 10, this is really the norm for the series. The battle characters tend to be slaves to the gameplay system.
True, but the job systems for FFIII and FFV at least were indepth. FFVII pretty much defines its characters by what materia is equipped to them, there is no real depth or challenge to learning spells or summoning, it's pretty much free for all.
FF6 has this problem too.

I remember being challenged by FFVI, I don't remember being challenged AT ALL in FFVII (never actually grinded or anything like that, while in FFVI I had to level up a few times). FFVI is pretty easy too, but I personally thought some bits were challenging. (fighting octopus for the first time, Floating continent, last dungeon, a few boss battles; not to mention in the world of ruin, you
could potentially get yourself into a very hard time if you go to one place too early example.)
This is one of the big reasons why I'm in favor of a remake of 7. I think the abysmal translation the game received had a very severe impact on the storyline. Even while the PC version cleaned up some of the dialogue, it still reads like ass. A remake would pretty much guarantee a new, competent localization overseas, I'd like to think.
I really don't think it's the poor translation alone that really screws up the storyline, I think its mainly the execution of the concept that does. But the weak translation really makes it a disaster all round.