I started from the LADYKLLR.MAP file from the DNF 2013 mod, which I copied into my main Duke3D directory. I deliberately avoided to add any .ART file, so that the HRP would kick in, even though that would result in several textures being rendered as black. I added several colored Polymer lights in correspondence of the street lights in the main boulevard, I replaced the custom street texture (which used to make the street look black) with the standard Duke3D street texture, then I launched the level from the main game.
So the frame rate does take a hit, but I disagree about the level looking uglier. Here are the results:

