Do any of these newfanglements allow the user to configure right-click (or middle-click, for that matter) so that it doesn't also require a left-click? I tried some third-party remapping programs, but none of them even detected a solo right-click.
That, for me, was half the problem. Right-click should not require touching the tip of the pen to the screen (ie: left-clicking), but should work whenever the barrel button is pressed, as long as the pen is 'hovering' near the screen.
It should probably be noted that the three-button mouse has allowed fully independent left/right/middle-clicking for as long as it's been in existence, and Wacom's digitisers have allowed 'hover clicking' for 20 years or so. It seems safe to assume, then, that for most users who have prior experience with a Wacom or similar digitiser, or for anyone who uses programs that require a two/three-button mouse, independent left/right/middle-clicking would be the preferred behaviour, if not an absolute necessity.
Personally, because of the wacky button configuration, I found the SP3 completely unusable for serious or even casual graphics work. I considered keeping it just for programming, but I found (Microsoft's own) Visual Studio largely unusable on it as well, because it can't be configured to ignore the touchscreen.
Another commenter mentioned Mudbox & Maya; I don't think those would be usable without having three whole buttons on the primary pointing device.