16" rims on a E90/E92 is just too small from a look perspective.
I found that even 18" on these cars look small. I changed mine up to 19's and it looks amazing. Fills up the wheel gaps. 18" looks nice on a E46.
I'd personally put snows on the 16" factor rims. Keep with the 205 width tire size for the snows... they will really dig into snow if needed. Better tranction than 17/225's... Think Ice Skates vs snow shoes. You want tranction...
I'd order new rims and 17/18" summer tires...
There's no point in going 17" Snows.. you want thin snows!!!!
Stance is not everything in the winter.