I don't think you'll have a problem. I use virtually only vintange boards with 2KRO, and game with all of them just fine. Most can even do WAD, shift, control, space, all at once and that's more than are actually usable ingame. So I'm not really seeing where that's an actual issue. This set of keys is what I test for games like Warframe and Mass Effect 3 (for all diagonals along with the others).
I've played through all the FEAR games with default keyboard mappings on a Model M before (same matrix as that unicomp, probably), and that's also quite a few keys to do all the time stopping and whatnot.
Things like 'WED' generally do not work on a 2KRO board, but that's generally not needed. I've only run into a few that really only allow 2 keys at once, and I'd agree that that is a bit much. But most of the time 2KRO is totally fine. So yeah, if you like buckling springs no reason not to.