Reminds me of the Defender of the Crown contest.
http://retrouprising.com/contests/cl...s-crown/t8248/
Instead of playing for a bunch of trophies, DotC was a contest in which the chooser picks a game and both players play for the the best score. We have a new wave of mods so it would be cool to see how it goes.
I like your idea too though because it doesn't just limit challenges against mods.