I would love to see DC Heroes, and Torg and/or Masterbook. I've been trying to teach myself the Authoring Kit, but it's slow going. I understand some of the concepts, but the examples in the wiki are a little hard for me to follow. I'm probably just dense.
Anyway, Torg, Masterbook, DC Heroes (or Blood of Heroes) would be games I'd like to see. Though, as they're all defunct, I doubt you'll be able to get licenses for 'em...