I think having Better technology, and more possibilities can have a detrimental effect, as was proved with UT2kx. Alot of the Textures, lighting, meshes and skyboxes were poor quality and lazy compared to the limited tech UT99 was done on. The weapon effects on that engine should look better than UT99, but they don't, they look worse, just compare Pulsgun with Link, Enforcer with AR,
The Old Flak cannon, with the new Flak cannon.
UT99 lava and water effects were also much better looking and more colourful, the UT2kx procedural mesh water are too gaudy and large too look like water. I hope epic doesn't go the route of Half Life 2 by making the water too realistic, clear etc, I'd like to see colourful imaginative water like in DM Turbine, AS Frigate and in the Original Unreal, just done with better tech this time!
Having procedual textures in UT99/Unreal gave it a unique look unlike any other shooter. Now Epic/DE mostly port stuff from Maya/3d studio max but it looks to like stock sci-fi stuff that you could see in any FPS.
Having less options confines designers too make good choices, and be genrally more imaginative and creative, it cuts down on excess, like how excessive the meshes were in UT2kx (you heard me! DM Icetomb)
Compare the Skaarj mothership in Unreal, and the one in UT2004, its unbelivable that the old one on inferior technology is far better and feels more like a real place!