SAT meant a huge deal, at least in my book... you need to have it all balanced out... I mean getting a solid GPA should lead you to a solid enough SAT if you prepare well, it's a dead easy exam... it really is.. at least when I took it, now i'm sure things are much different and it's much harder, but it wasn't really a sweat at all.
Again, there's no magic proportion, get everything right, from sports, to extracirriculars to grades to SAT... and be sure not to be like these other idiots who joined everything and wrote it all down... do like 2-3 things DAMN well... that's what counts... i did many things but always scored high in each one or always took more than enough responsibility and that showed... so keep that in mind.