> 2. Multimonitor support is a real pain to configure...
Are you using a somewhat recent KDE? At least on the three machines that I regularly use, the management UI looks like [0], and works at least as well as the one in Windows 7.
Likely my problem is that I really like tiling WMs, so end up trying to make my world work with something like xmonad or even dwm. It's entirely possible multimonitor is satisfactory with KDE, and maybe I should give that another shot.
I do, however, know that OS X does font rendering so much better that I have trouble with pretty much any alternative.
Well, if by "better" you mean "much worse". OSX font rendering is basically inconsistent, blurry blobs (yes, I've used OSX for years as well as various Linux distros).
That's fine if that's what you like, but don't try and pretend that it's in any way objectively "better".
I do, however, know that OS X does font rendering so much better that I have trouble with pretty much any alternative.