I have to say character design. After that story and last graphics.
In this case the game already has great great gameplay.

If all youre gonna say is it doesnt matter because the game is great than dont bother posting.

Personally if the game is good I still want the other things to make it better. Brave Story is fun but character design is horrible and story average. The graphics are nice but I dont care about graphics.

Atmosphere, which is a combination of setting, story, visuals(doesn't have to be technically impressive to hit its target) and many more small things that make you feel like you are playing in a real world.

I agree with sc94597.

Story would be my choice, but games without story it will probably be visuals. It depends a little bit on the genre.

art direction, story, quality of voice acting

Me too, though I'd put art direction at a very close second. Maybe we could just lump everything into the "immersion" category and call it a day.

After gameplay... I'd say pacing. It's the most important element of the story and the most important element of the gameplay.

Nintendo characters. In fact it comes before gameplay. I can't enjoy a game if it doesn't have Nintendo characters in it.

As mentioned elsewhere, the ability to break glass is most important to me, even moreso than gameplay itself. I refuse to play games where there is no glass to be broken (or worse, where there is glass that CAN'T be broken).

Style. Pizzaz. Panache. Verve.