I use a Surface Pro 1 for my MF digital tethered work, and love it. I can run full version of Capture One Pro software, (free in DB edition) tethered to my IQ series digital back via USB3, and work on location, to see 100% accurate focus check, DOF, etc.
Yes its a little bit heavier than ideal, but right now there is literally *nothing* else with Pro processors in the tablet form. Until Apple release an iPad Pro (possibly never) this is as good as it gets for full power tablet form. I appreciate there are 'convertibles', but a locked on keyboard is just a nuisance in situations where this shines.
Many of your complaints are about Windows 8 changeover in general, which you cannot blame on the Surface machines. The changes from Windows 7 to 8 takes a bit of getting used to, but once you do, seems a useful OS change, especially in touchscreens, like this.
IMHO, the Surface Pro's screen is much too small to do Photoshop work. There is a better slate tablet on the market. It is the Wacom Cintiq Companion that runs Windows 8.1 Pro.
It has a 13.3" HD (1920 x 1080) IPS screen that is touch and stylus sensitive with 2048 levels of pressure and pen tilt recognition. It has an Intel i7 processor,Intel HD 4000 graphics, 8GB ram, 512 GB SSD, 802.11 b/g/n WiFi, Bluetooth 4.0, two USB 3.0 ports and a mini display port.
I have been using mine for about a month now and it breezes through any Photoshop or Lightroom job with ease. Coming from a Mac OS, the Windows 8.1 OS takes some getting used to.http://cintiqcompanion.wacom.com/CintiqCompanion/en/