Ok, first thing is that for the scholarship you should have some sort of extra curricular activities. The Navy looks for well-rounded people. Which means sports, clubs, or jobs. If you just want to be part of a NROTC Unit and dont want a scholarship then its not as big of a deal. A pilots license has no bearing on your competitiveness for a flight slot. If it did, then people who couldnt afford flight training would be at a disadvantage. When you get sent to flight school the Navy equalizes that out anyhow with IFS. The main factors in getting a flight slot are whether or not you are physically qualified, your grades, your extra curricular activities, your ASTB score, and your NROTC Unit's impression of you. If they dont think you can hack it or whatever, then they wont put in a recommendation for you or try as hard. As for the being tall part, that depends on what aircraft you want to fly. The Navy has restrictions on different aircraft depending on what the cockpit accomodates, and what type of person certain ejection seats will work with. When you take your aviation physical, they will measure your height, arm length, sitting height, etc. I do not know what the limits are as far as aircraft, but my friend at VMI was 6'4" or something close to that, and he had to submit a waiver for his height.
Gary