So I just bought a 2015 Audi Allroad and am going to get started with some mods, notably suspension and wheels. With wheels, for the sizing, should I be looking only at 19x9 or 20x9 or are there other widths I should look at? Also wondering what the appropriate ET's that I should look for.

I have seen ET26 on a number of posts, when I am looking for wheels in the classifieds, are there other ET's I should look at?

I am coming from a B5 S4 Avant and have a number of Avus wheels, so now I need to start looking for new Allroad wheels. Any recommendations are welcome. I am interested in getting a set of the RS5 rotors I think.