I recently wrote a time tracking project. Each time tracking entry belongs to a time tracking "profile", which can be controlled by the default time tracking class or by an extension thereof. I also wrote an extension, the Quickbooks extension to get Drupal time entries into Quickbooks.

I'm hoping you - or someone else - will consider writing a similar handler that leverages your Freshbooks API so that I can make sure that the basic time tracking functionality is extensible enough before it's too locked in.

This is potentially helpful but a little off-topic. I will not be offended if you "won't fix" this out of hand ;)