I don’t think wacom drives will work because its N-trig digitizer. Basically the problem is that you have press really hard to get a decent mark in zbrush or fresh paint. Sketchbook doesn’t require as much pushing of the pen.
I just got the tiny wedge keyboard. Windows 8.1 Fails to connect or pair with it. I have tried through control panel add device, and through pc and devices bluetooth pairing options. How did you set up your keyboard?
Update* Got the keyboard to work. I had to install about an hours worth of windows update which were not available at first. That resolved the keyboard not pairing. When it paired I had to input numbers and that worked. When you have the keyboard covered with the included cover it sometimes will turn on and will drain batteries. I also think the battery life of the surface will suffer while on bluetooth. It seems to drain faster that way.
For the sensitivity that requires pushing hard on the screen to get decent line weight, that’s going to be resolved in the next month with a microsoft pressure curve software update. In zbrush there is a setting for tablet pressure that should help, and you can also manually adjust the brush embedding values to raise the stroke up more.