By 'heavy' he most likely meant having an overwhelming amount of windows/information on the screen.
The goal of almost all UIs and games is to have a clean interface that distracts less from the gameplay. Having modular windows, popups, and menus does that. In that sense, the idea on the OP would probably be a "no", but I'd like to see proper UI/window scaling for non-standard resolutions similar to other games.
http://www.wsgf.org/dr/world-warcraft-wrath-lich-king
Check out the Comparison Screenshots section, they have one with Eyefinity, which is what ARR should be doing as well. That way, if anyone wants to clutter up one side of their screen with a bunch of inventory screens, they can do that.