Those three are top of the crop for me. I'd say it's a toss-up... the Rezound if you like the Sense overlay (which I do), Nexus if you want a mostly unencumbered operating system experience (as I prefer), or the RAZR for solid (and predictable) hardware. I would say the RAZR Maxx trumps them all only based on battery life. I carry the predecessor to the Rezound, and envy the fact that it doesn't have the quirks and bugs that the Thunderbolt had. I also carry the regular RAZR, and find it to be quite excellent, even without the Maxx battery.
I've preordered a Galaxy S3 to replace my Thunderbolt.
Hobble mentioned the RAZR HD - no need looking into phones that can't even be purchased (and haven't been announced - remember the FIRST ... (continues)