Games that play well in VASSAL? Favorites?

So a buddy of mine and me regularly play in Tabletop Simulator. We like it, but he’s very into wargames so we found VASSAL. We’re interested in games that are both good and play well in VASSAL. Particularly playing via email would be cool for us. What’s your favorite? What do you play often? Recommendations?

We love all games, but for example we were looking at C&C ancients, have recently played Res Arcana and Wingspan.

Thanks for your time.