Well, battery monitor / charging is mostly done by ToastBucket (but not yet implemented in our test image), speakers being overdriven seems to be a non-issue, as they overdrive if you raise the ALSA volume to 75% or higher - and according to the docs I found, 75% is 0dB, so anything above CAN overdrive (even some of my older laptops do that).
And this happens regardless what speakers I connect - so it has nothing to do with the sealing.
The hang on restart has not yet been looked into more, as no dev had the time yet. Nikolaus knows approximately what it is, as it reboots if we disable some hardware, so we have a good clue.
Power Saving is partly working, normal battery life right now seems to be 10 hours, but that depends a lot on brightness settings.