I don't have any strong feelings about this either way, but the main question in my head after reading this is: - Are the differences SIGNIFICANT enough to sup

I don't have any strong feelings about this either way, but the main question in my head after reading this is: - Are the differences SIGNIFICANT enough to support two (three?) different codebases? A lot of your points seem to be more about building in configurations/plugins versus a completely different (core) storage format. For instance, adding in separate plugins for different dictionary compressions, or being able to specify the block read size or schemes. I would just think you may be spending a lot of time reinventing 80% of the wheel and 20% on 'memory specific' functionality. (I'm naively oversimplifying, but its something to think about).