I have been fishing and tying jigs for 15+ years and I am hard pressed to confidently say that jig head color makes ANY difference to the fish on a regular basis. That said there may be certain times or jigs where color makes a difference but not enough to make me want to paint all my jigs.
I'll give 2 examples: I had a paint jig head with marabou body get beat to hell in a couple of trips...paint was all but gone but it continued to fish well. I tied up my last white headed jig just before the end of the season. I usually tie at least 3 of each color pattern I start so I tied one with a painted head and 2 without. The painted head jig was killing em until a fish ran into a log jam with it. I tied on the same pattern with a bare lead head and continued pounding on the fish.
So is the slotted bead an answer...a better answer would be go to a poured lead head. As well, the beads (pinned or slotted) are pretty light, too light to really twitch ie spin cast. Yyou have to float fish those jigs...go to a 1/4 or heavy poured lead head and then you can float or cast those jigs due to the added weight compared to a pinned bead.