All the stuff I get is either free-as-in-libre or something my wife is going to enjoy using. Surface is neither, with the bonus that whoever was in charge was clueless enough to load it with 40G of software.
8.1 for outlook was the real clincher. Before I hadn't really liked any tablets I'd used.
But now this thing really does go everywhere. Office is rather integral to my workflow, every alternative I've tried hasn't cut the mustard. Now when I'm away, I've got my laptop and my 'office slab'. The touch cover actually works rather well, I won't mind typing out a good long email on it without wanting to slam the device into the wall (which my Nexus 7 makes me want to do).
It is also remarkably adept at just working with anything I slam on the USB. I can use it to backup my SD cards to a USB HDD when travelling (having lost an SD card last year half way through my holiday I'm paranoid!) or I just plug in my USB headset for Skype. It can browse the web including pages that have bad touch events (ie menu comes down on mouse over, not mouse down).
And it does flash.
I've only got an iPad 2 to compare against for speed, and yes whilst I'd like it faster, it isn't problematic.
I can't really see a lot of the hate on the Surface, as a product it isn't really there yet. But neither is my iPad or my Nexus.
I guess many things you list are orthogonal to what I would want it for (and I am quite pleased that there's no more Flash), so I don't see it as an improvement to the iPad, nor is it any more open.