Also I notice the motors make a fair noise even when they are not moving, but just under control of the board. Is this normal?
yep, thats pretty normal for that board

iv also had a ponder on the idea of adding a lathe head of some sort
in theory you could have a row of turning tools on the bottom of your Z axis for and easy tool change, might be worth the effort if your making a big batch of parts
iv not fleashed the idea out yet (depends on a job) ill post if i have a crack at it :)