Good call leaving it standard as possible.The only thing thats not standard on mine is the exhaust which is a full sebring stainless steel jobby.
Not sure the alpina rims will go so well on a compact as they do on other bmw.
However some nice sunflower rims or m3 motorsport type will do the job.
BTW what size tyres do you run on yours ive 225/50/16s Dunlop all aroud and seem a little to big.