I agree with Referee in not retaking the MCAT and school selection. Thats likely not the reason you didnt get in if you applied broadly.
I'd work on interview skills as well. Its possible you may have came off a certain way which may not have been appealing to adcoms.
As far as the research split, most big programs are looking for people striving for 80/20. It's a mistake i made as well during my interview process as well.
On a personal note, i think its ridiculous to put that much stock into a young kid's anticipation of what their career will be like 10+ years before it actually comes to fruition.
Even some of the most staunch 80/20'ers can end up in private practice because in the end no one has a crystal ball to predict what 8 years of schooling and 3-5 years of a residency do to a persons interests.