www.matweb.com

you can look up properties of any material, granted you might need to know the technical name, and figure out your self which would be a better choice. There is ulitmately an optimized point, where a rim of x-diameter with a tire sidewall of y will perform better than a rim of s-diameter and a tire of w-sidewall. An example of this is with the S2K, when the y went from 16" rim to a 17" rim they actually softened the suspension up a bit. They final result was a better ride quality but about the same handling characteristics