Just for starters, I think I would look at NVidia Quadro or AMD FirePro, just to have 10 bit support in case you should want that down the line. Some of them are of course ridiculously expensive, but the lower end is quite reasonable.
Currently there is a wave of users with AMD cards who can't get OpenGL to work in Lightroom/ACR (myself included). Hard to say what the eventual outcome of that will turn out to be, but maybe NVidia is a safer bet for now. Seems to be no problems there.