With Final Fantasy, you got the best of both worlds, so why would you want to choose?

On a first playthrough I'll probably be focusing on the story and overall experience, as I learn the gameplay system as I go. On subsequent playthroughs, it's definitely more about the gameplay as I try to maximize my strategy and find the hidden stuff that'll make my party even better.

However, sometimes you even get more out of the story on subsequent playthroughs. FFXII offered so much depth and material to cover in the gameplay, but I learned to appreciate the story more and more as I played.