The ability to require an email address and use the current user’s if they are logged in is already built into the plugin. It is one of the options when you create a form.
As for pulling data from the extended BuddyPress plugin, no plans to do that.
This plugin supports any Google Form which means the fields can literally be anything that the person wants to design the form to be. There is no facility for mapping existing WordPress user data onto the form fields. I supposed it could technically be done but there would be so many caveats and restrictions that I don’t think it would yield anything very useful.
Unfortunately Google Forms don’t have an API. Google Docs do but Forms do not. The only way to interact with the Form is to do so interactively. The plugin mimic interactive behavior using the WordPress HTTP API.