Awesome work.

I have been working on an open source API to accomplish similar things (specifically just re: aggregation of data from disparate sources): https://github.com/jdjkelly/quantify

It's Rails + Postgres, and so far aggregates meal, weight, and sleep data from Withings and Fitbit - but I've been focussed on building out a framework to easily aggregate many, many more sources.

Maybe we could find a project to work on together - contact is in my profile.