Hey I'd love something like that, I'm browsing around for the mod Xraid status ( i think it is ) which just shows the main tank and main assist targets ( If I'm thinking of the correct addon). I think it would be really helpful. Lol that just got me imagining what the screen would look like with an added screen full of unit frames when you have to AoE
EDIT: Maybe a set of 5 or so mini frames that includes all targets with a symbol or if there is only a few symboled targets the remaining empty mini frames fill with unsymboled mobs in order of remaining health? just adding /end blabber