D.W.
Our son will be 4 in a few weeks and is very similar to the traits you explain in your son - just his personality. He'll be every girl's best friend in high school and will be the "good guy" because he's so sweet and sensitive.
He loves playing with cars, Tonka trucks, etc. He's just very sensitive. We have several kids on our street who are all in the same age, and I find he's pulling away from the really rough boys and gravitating more towards the other kids who prefer to play "pirate" and tell stories.
My husband and I both have very strong personalities and are very independent. He's a different personality, and we completely embrace him for it. However, it is hard to see the boys he's played with the past 3 years stop being as interested in playing with him, but I can't force them to like him, and honestly, I don't always like how they're behaved, so it will work out OK in the long run.
Good luck!