story is VERY important, i walked away from/pawned to of the 'biggest' titles late in the PS2 life (GoW 2 and FF12 in case your wondering) cause both left me no reason to care enough to WANT to see it through,
one had an angry jerk acting like some one took his favorite toy, I've no tolerance for a tantrum RL, sure as hell don't have it in me to give a shit about one in game, where as the other *sighs* basically bored me to the point of not caring
where as the Legacy of Kain, from a game play stand point, very eh, at best, but where it shines is in the story and narrative, i was more then happy to put up with it rather dull combat for the next bit of story (though, using Kain to fling Seraphim solders off very high places or into something sharp and pointy never got old, if nothing else you do get some rather fun ways to off people, but i digress) and serves as one of the ONLY examples of a story i'd pay for to have in book form, like good money
though on the flip side, art can make up for or enhance story short comings, i love the Shin Megami Tensei seires

Nocturne being my fave of all of them, but admittedly its eh, plot wise, but it makes up for it with it in how its presented, in visuals and music, and a some what non linear feel (seriously, it can be confusing some times in that game >.> when i wasn't doing every side quest i could >.>) which keep me interested till the end with '0.0;;; OMFG no way' ending i got
anyway, thats just my thoughts
i'm willing to let gameplay issues slide if the story is there, not the other way around