Where you plugged in and fully charged?
Did you try it with and without the keyboard?
Yup, Yup, Yup, Yup... with and without keyboard, 100% charged, plugged in, not plugged in, tried doing the update through Windows Update in the control panel on the desktop...We'll see if all of these latest updates install now. I tried the hard boot or whatever with the power + volume up (I think it was up), all to no avail. I got ZERO complaints about the performance of my surface, so in no rush. Just irks me a little that it doesn't install like its supposed to. Mines a 4300 if that matters at all.
As for the OP's issues, I'd try Microsoft Support, you can do a chat with them, that's what I did to get suggestions. My gut tells me that they will have you try a few basic things and then suggest a refresh. Worth a shot though, you never know!