How about taking the same span and pitches from the ball that you're getting out of ok (but just a little too much behind it) and try reducing the left lateral in the thumb by an 1/8th. I typically like to only change one variable at a time so we know whether or not it is effective.
If that doesn't workout, then I'd leave that lateral pitch and start increasing the reverse pitch in the thumb to help you exit quicker and hopefully let your hand rotate as desired. I remember your thumb being on the stiff side and not having a lot of flexibility so I'd even go with an 1/8th more which would bring you to a 1/4 reverse total. Let me know if I can be of any more help to you and great hearing from you.
ps. Since I saw you last, I think I've moved twice (3 if you count moving the shop) so I'll have to go and try and dig up your old drill sheet to see what I did. Will get back to you when I find it, thanks.