18" or 19" winter wheels plus tires combination are a relatively cheap option.

This winter, I went to 20" Pirelli Scorpion snow tires and we've had no snow to speak of!!! Only one day with 6" snow the whole winter so far (I'm not counting Halloween because I didn't have the snow tires on yet).

So I can't tell you if the 20" tires are going to work as well as my former 18" snow tires did. I'm going to some testing (in a safe area) as soon as we get some decent snow...