With regard to “why do I have to exit messages to scroll through a list of my contacts”: are you aware that you can start a new message and either start typing in the “To” field or tap the + button to bring up your list of contacts? Is there something else you’re looking for?
CanJS, the MVVM part of DoneJS, is currently coming up to its third major/breaking version. I think that’s a pretty good track record for us/Bitovi.