I work on Moai - we just shipped 1.0 last week. It's designed to be a minimalist, open source framework for game development. We think that's the best approach for experienced game devs - look at Bungie's Crimson Steam Pirates on iOS and Chrome for an example of what you can achieve. If you need a higher level scene manager, then check out Rapa Nui for Moai at https://github.com/ymobe/rapanui