Dear Damien, 

First off, no matter how smart you are you will be challenged in the priesthood and will use all your gifts to the extreme, (just look at John Paul II); so forget about the thought that becoming a priest will be tantamount to throwing away your talents. If God wants you to be a priest and gave you intelligence at the same time it is because you will need and will have to develop that intelligence in order to do all he wants of you. 

About being a "goody-two-shoes", I wouldn't give it too much thought. Not everything your friends may consider normal is going to be the best for you, and there is something wrong or weak with their own faith if they say your behavior turns them off from religion, so don't sweat too much about "appearing" normal. Just have it clear in your own mind what is right and what is wrong, know why you do things, make your own choices, live your own life well, join in what you can of what your friends do, opt out of what you see is damaging or just plain stupid. That is "being" normal and it's much more important than "appearing" normal. 

It is interesting that they would ask you if you have a vocation to the priesthood. It may be that they recognize that your behavior is right, but it will get them off the hook if you say you are going to be a priest, because they aren't, and so will feel excused from the same standards. So I wouldn't answer yes. Instead I would ask them why they ask - so as to have the opportunity to say that the reason you do what you do is because it is what is right to do, not for any other reason. Maybe that way you will jog somebody's conscience a little.  

God bless.