i haven't checked this thread in a minute, so 1st i want to say my bad if i offended you kanno, that wasn't my intention.

but to answer your question, i would say I's more influential on the genre. Like you said, there was no RPG like it at the time, everything was about slaying the dragon and saving the princess, and even though the time loop scenario seems small and lame by today's standards, at the time it must have been groundbreaking. Other RPGs at the time focused on traditional medieval european settings whereas Final Fantasy was true and good romanticism, taking the folklore of many different cultures into one story.

As far as the FF series, I think they both are the two templates that every game is based off of. II went in a completely different direction than I. in I, the characters aren't really important at all, it's the world around them that is. The same thing happens in III, and in V, VII, and IX, the characters aren't as big or powerful as the circumstances which made them. They are representative of those things, and in the case of I, it was the crystals.

On the other hand, in II, 4 unlikely heroes step up and save the world. In this respect, IV, VI, VIII, and X are all about people who take matters into their own hands and change the course of history.

I think that's why in all the odd numbered games (I, III, V, VII and IX) the fate of the world is decided by crystals, in one form or another. In the even ones, there are no crystals. I know in IV there are, but they are a product of the "other" world, not of the one which all the main heroes hail from.

Which really makes me think about XII and how there's competing forces about whether or not to put history back into the hands of man, and whether or not that's what really happened. I don't know, I think i've rambled too much to start getting into the Philosophy of Final Fantasy.