He recently turned 11 and is one of the best in his age group at their club. He has good control, can provide good ball spin but need a racquet that provides better speed/power, he has a Wilson 6.1 Team 18/20 now and we strung it with natural gut/poly (46 lbs/21kg)) and it got better but I'm not satisfied. He is short for his age, but very strong, I was short also but caught up in high school and went by my friends. I think that next racquet may well have 16/19 string pattern. What racquet would you recommend?