"Is there an easy way to filter out 1v1 games on vdip for your stats?"
There isn't, I did it manually as well.
"One issue I think that will play into this is that the games on v-dip are not nearly as well designed as the classic version."
This is the arrogance of the webdippers. Classic is not the best map.
Sengoku, Fall of the American Empire, Milan and Europe 1939, the symmetrical maps, Verdun and Hundred are all more balanced.
1v1s, 1066, Hundred, Verdun, zues 5, colonial, Imp 2, 901 and WW4 are more enjoyable (in my oppinion) games.
Classic is the original, but that doesn't mean its the best, over the years people have made changes in hopes to make a better, more balanced, more enjoyable game. Not all of them succeeded, but many did. I will agree that most of the variants on vDip are not as good as Classic, but some of them are, and the arrogance to assume that Classic is better without actually trying the other variants is something to be noted.