This was literally
decades ago, but a mate was in the NSW Mazda Car Club and I went to a few club driver-training days with them. I suspect they may be the sorts of thing that's being sought, they were more about car control than they were about good driving, and all 3 times they had a couple of professional racing drivers on hand to do the coaching.
Apparently John Bowe was one of the trainers the year before I first went, ie:
So maybe a physical car-club could be a good approach? Wasn't run for profit so was considerably cheaper than the courses I attended.