The good news is that a score of AA 20 and TS 21 is solid. HOWEVER, some schools "may" see your RC and PAT scores as a red flag.
During my UoP interview, my interviewer was impressed with my 24 RC score. Then, we spent 5 minutes discussing how I just finished reading a book on speed reading and how it helped me get even faster at reading. A few days later I got accepted to UoP.
Conclusion: UoP cares about RC scores.
In addition, UoP also has one of the highest PAT averages in the nation.
Conclusion: UoP cares about PAT scores.
During my UMich interview, I was asked about my "proof" of my manual dexterity. I explained that I am artistically and musically inclined, and that correlates to my high PAT score. I was accepted to UMich a few days later.
Conclusion: UMich cares about PAT scores.
During my UIC & USC interview, I wasn't asked about either of my RC and PAT scores, but I was accepted to both schools. Also, both of these schools only have "ok" RC and PAT averages.
Conclusion: UIC & USC don't really care about RC and PAT as long as the rest the application is strong.
Overall conclusion: Different schools place different emphasis on RC and PAT scores. However, I would be nervous about RC & PAT scores of 18 or lower. In addition, there are probably a ton of SDN'ers that had completely different interview experiences than I had.