I think Microsoft would be happy to hear that you realized how powerful it is as an all-in-one device - tablet, laptop and desktop, but may be didn't think that someone would take it to the extreme and have that many devices connected simultaneously. That being said, you may want to try something other than the MS Dock. I have the Plugable UD-3900 and it has 2 USB 3 and 4 USB2.0 ports on it and it has been working great. I haven't maxxed out the ports, but it might be an interesting exercise to try it out sometime.
I am waiting for the SP3 since I returned my SP2, but I am hoping that it would be powerful enough to handle almost everything I throw at it.