Heh, you're doing this thoroughly :) I'll stay with the initial design, because of the very small text in the buttons in 4 (and it makes the line height larger in my browser, because I set a larger minimum text size), and because I find it looks strange when buttons are zig-zagging (whereas the links flow with the text).
I noticed one glitch with the immediate removal: if you revert one field, then revert another while the auto-preview is fetching (the wheel is spinning), then the second field re-appears due to the auto-preview, and re-disappears at the next cycle. I think that's ok, the immediate feedback of the removal has enough value that we can tolerate this small glitch.
Patch applied in [11077].
