I think the premium pack should be standard, maybe without the leather. Ambiance lighting I think is a must especially if you drive at night a lot. Also I don't know if your interested in the pano moonroof but if you are along with the xenons.. Those equipped on a 28i makes the price difference with the 35i only like 2k with all that and more standard...
Ok I'm getting carried away, if your on a budget, why not check out the X1? That's quite a bit cheaper and just as cool IMO