Actually, I would steer you to Mer. Mer just got rebooted a month or so ago as the future of community-driven MeeGo Core. The Cordia UI is based on Mer. The KDE folks' Plasma Active user interface may run off Mer. I know Mer has had a disappointing history with its past incarnations, but it seems to have a burst of momentum now and the promise of taking the best of what came from MeeGo and running with it in a fully open, community-driven way. If nothing else, consider talking to Stskeeps about your plans, and he can tell you what pain & suffering lies on a path like this.