I got a couple of these for my son.
Stash Sports
He doesn't have a problem with his mitt, but was getting stung every once in a while when playing long toss. They have really helped and he says they don't bother him in the glove. We got the fingerless versions.
He uses the Akadema mitt when catching and it does have plenty of padding and a special wedge between thumb and index. Nice mitt. When he starts catching faster pitching he will have the Stash mitts to help if needed.
Tim