I never took a lesson or got coaching until I was 18. Got to top 50 in my section in the 18s and made my college DI team (middle of the A10, don't play anymore). I played basketball, baseball (pitcher), football (QB), skiing and soccer since I was 5 and started MMA/boxing a year ago and already competed in them (won 2 boxing and 2 mma fights). Had two rotator cuff surgeries and tore my distal bicep tendon last summer and needed surgery. Also have had 7 concussions so I'm legally brain damaged.
Either I am athletically gifted or I am a freak athlete now because of all these sports. I was always naturally good at sports and pick them up quick. If I could go back in time, only focus on tennis, and receive top quality coaching then I might have a chance. Most of my game is based on using my athletic abilities to outrun, outlast, and outhit (overpower) my opponents. My serve would probably be weaker because I wouldn't be playing baseball and football. I might even be worse off.
Also I have never been focused on tennis. It's not my favorite sport and I may perform worse when I don't have other competitive sports to distract me. I might even quit.
So basically I have no clue if I'd even be better than I am now.
Head Youtek Prestige Pro 4g @12, 6g @ 3&9, 16g @ buttcap
Genesis Spin X 17g or Typhoon 16L 70#