You sound very mature and thoughtful for your age. That's a wonderful thing.
It's also wonderful that your wise parents gave you the opportunity to choose for yourself.
Please don't decide yet. Let your sexuality develop naturally. That shyness and inexperience is one of the most beautiful parts of your life. It's called anticipation, and you'll never forget the feelings of your first sexual encounters, when they come.
Shyness also protects you from inappropriate partners and timing. You'll know when you DON'T want to be involved.
Meanwhile, calm yourself with your excellent abilities of observation. Notice all your peers, not just those who pretend to be 'older'.
The best time to choose is AFTER you have thoroughly explored the world of your adult sexuality.
Think of it, you could have the best of both worlds, and no regrets.
Have you ever wondered why so many women seek UNcircumcized men, or why it is a question at all?
Patience and courage, my friend. You are a fine young man. You will be a fine lover.