yes black purple and blue combos do work, I think the reason you don't hear more about them is so many kokanee fisherman are hung up on the pinks oranges etc. No question those colors work but I would advise you not be afraid to think outside the box a bit and go with the darker colors especially on cloudy days.
Silver bullets love those pic's you posted and I have just one thing to say.....you have way too much time on your hands hahahaha....joking!! those are some good looking lures and jigs