If you are coming and going a lot it could be annoying and the Pro might not be the ideal device in that situation. See this thread here
http://www.surfaceforums.net/forum/microsoft-surface-pro/3598-ext-screen-magnification.html. Hopefully a docking solution is in the future. As it is though you are going to have to pulg and unplug the USB, the monitors and probably the power. The resolution change is only one more part of the process but I don't see frequent coming and going being the best use case on any device without a proper dock. Maybe this is a generation 2 item if MS sees that there is a large demand for multi monitor setups with this form factor.
I don't think the keyboard makes the Pro a mediocre ultrabook. Is that all it takes is a bad keyboard to be a mediocre ultrabook? Many people find the touch cover sufficient for even heavy typing and if not there is the type cover which many people find to be one of the best keyboards they have ever used period. I might not get what you are saying but I just don't see how the keyboard makes the Pro a less than optimal ultrabook.
On the tablet front I suppose it does suffer some "compromises" in that it is not quite as small as a "typical" 10" tablet and it doesn't have "tablet" battery life. Over all though it is a PC in tablet form and the fact that you can use it touch only without a keyboard, in landscape and portrait mode and that it is the most mobile form factor of any other PC makes it a tablet in use case scenarios like no traditional laptop can.
I guess what I don't understand is that if you don't want these features then you shouldn't be looking at the Surface Pro. There are a lot of other options out there if you need a laptop or a tablet specifically. It certainly isn't going to be the right device for all people in all situations. At the end of the day though the Pro is by far the best device available that has the power of an ultrabook and the form of a tablet and there are only "compromises" if what you really need is something different than what the Pro offers.
It might be a half empty/half full type of thing. Some people see compromise and some see features. I would consider the multi monitor situation, single usb port, screen size, fixed memory, ethernet port, optical drive, weight and battery life compromises of size/form factor. You can't have all these things if you want a small, sleek form factor. I don't consider an alternative type of keyboard to be a compromise of an ultrabook though.
To me a compromises of an ultrabook would be missing things that make it an ultrabook, like using a less powerful processor (Atom or ARM), 1 or 2 GB of RAM, being too large (excessive weight or size) and a battery life of less than 3-4 hours. Things that would not be compromises of an ultrabook are things that are strictly related to form factor (loss of ports/drives, fixed memory, fixed battery) other than excessive size since portability is a hallmark of an ultrabook (otherwise it is called a desktop replacement
).
In my view the Surface Pro isn't lacking anything that makes an ultrabook what it is (a very portable, powerful computer with good battery life) so I don't see where it is compromised in that regard. Personally it doesn't fit my needs at the moment so I have the RT instead which would absolutely be a compromised ultrabook. That is ok with me though since it is a tablet in the sense of a small device with less processing power, longer battery and more portability than a PC/laptop, not in the sense of the overall form factor (let's not forget "tablet" PCs have been around for a long time it is only the very recent interpretation of the word "tablet" that means a class of devices smaller and less powerful than PCs/laptops).
Different points of view and devices for different people and uses
JP