Win 8.1 marketing should definitely point out how it's similar to Win 7, just improved.
Firstly I've used each beta of Win 8 (I still use Win 7) and I agree with a lot of the criticisms against it.
I've been trying out the Win 8.1 beta and I find it hard to go back to Win 7. it just flows nicely and the speed improvements are noticeable. I'll definitely be getting it and whenever a conversation comes up about Win 8 I let people know the improvements of 8.1.
I think MS should really focus on how Win 8.1 brings back the familiarity of Windows 7, just improved.
Their biggest problem is that their ads don't make you feel familiar with the product, I've had to google how to things when I first started using Win 8 beta.
The adjustments I've made (and I think should be standard) are
boot to desktop
made the background of the desktop and start screen match.
the addition of the start button really makes sense, it's not as jarring and is definitely more like the windows everyone knows just with a full screen start menu.
My home screen
I don't use metro apps except Photo Editor since it's awesome