"I'm amazed that we're on the same wavelength - we've had to build very similar infrastructure for ourselves"
Right, we hear that quite a bit. A few comments:
- Here's our Backbone sync adapter: https://github.com/Simperium/simperium/blob/master/javascrip...
- Dealing with subsets is a priority for us
- OT and versioning are generally helpful for managing changes/deltas
- We're using MongoDB for storage