I like to use CDC for spinners. Typically under a bit of krystal flash, antron etc. Also, Different small midge patterns.
One basically dresses like a small WD with a slightly larger thorax. Either a wing back version or spinner style.
I tie a cripple green drake and PMD with CDC as well, obviously the PMD gets used more. I like using green/grey biot with a bit of a build up for the green drake. A few moose hairs for a tail and a spun deer hair thorax and 6 pcs. of dunn-ish CDC for wingsUsually a size 10-12. Can work for flavs as well, but I like high floaters for late evening flav hatches.
PMD I tie a thread body, Dubbed thorax, microfibets or teal flank for a tail and 4 pcs CDC, depending on the size. They seem to get smaller the later in the season it gets, also depending on the water. Hanks fork may start out a 12-14 in early June and be an 18 by mid July.
Any of the later season micro-mays seem to catch CDC on my vice as well, especially trico spinners. Me gusta a good trico hatch. Nothing like seeing fish come up before the sun does.
Loop wing CDC flies are fun, but I think more for the tier than the fish.