you could grab one of the elite dragon textures ( or make your own ) and import the texture in as an eepanels2 background
add a script to the panel
Code:
local classification = UnitClassification("target");
if ( classification == "elite" ) then
THIS:Show()
else
THIS:Hide()
end
just create additional panels & codes for "worldboss", "rareelite", "rare" or "normal"