I don't have any arches (yet), but on the base of my mega-tree, which is 16 segments of PVC using 22.5 degree angles, I wrapped the front 8 segments, which are about 2' long each, with a 100 bulb string of multi-colored mini lights. It makes a terrific combination of colors. The minilights seem to take on the look of transparent candy. Next year I may try LEDs as I like the looks of that color.
The reason I did only 8 segments is the tree is on top the house and the back 8 are not visible from the street.