If you use the power lifts, have you tried ovals?  Or vise versa? 

You could drill a hole for the pinky finger, which (done correctly) takes some pressure off the other two fingers, and that could be a more permanent solution.

It's hard to know until you try it, but I would certainly not be afraid to try the extra pinky hole.  All of this assumes that your span and pitches are correct.

Have you had your span length checked? You stated that you changed pitches, but did you make any span changes? It could possibly be that your span is too long, causing excess grip pressure.

     Definitely needs a span check. Can't always go with the long theory though. I was having issues bruising under my ring finger nail. I started shortening my span as I thought I was putting pressure on my nail. I kept shortening in 1/16 incriments over the course of a few years. The shortening put excess strain on my ligaments and strained them from being too short. Lengthened my span to where it actually should have been all along with an added 1/8 reverse pitch in ring finger (currently at 1/4 reverse/away) due to lack of flexibility and have not had any issues for last 4 years. My son was having same issue and we lengthened him and his problem is clearing up. Take these recommendations and get span checked with someone who actually has eyes on your hand in your ball and give them feedback to resolve problem. Could be too long or too short.

John,

I had the same problem with my middle finger for the longest time. I was able to get some advice from Chris Barnes on this as he had the same issue during college. His advice was to decrease span length a touch and add away pitch on the fingers using oval inserts. I did this and it still happened. So I increased the away pitch even more, 5/8 away in middle, 3/8 away in ring and ever since then, I have not had this issue.

Hope this helps.