What current project would serve as the best starting point for such a game? All models and such will be done in Blender. Unforuntaly my personal programming skills are somewhat limited, but there are others in the project whose full-time jobs is programming.
You could try to take the PlaneShift source as a base as that is the most advanced MMORPG using CS right now. But it may be easier to use CS+CEL and start from scratch.