Roly is 14 months and still entire.
We have recently noticed him maturing and starting to assert himself more with other dogs - don't get me wrong, he's not aggressive at all, he's very non-confrontational - but just lately we've noticed he doesn't let other dogs walk all over him - he used to roll over and be all submissive but now he stands his ground and will be vocal if pushed around - he then walks away with his head held high! He is very gentle with smaller puppies but now tells them when he's had enough ear pulling etc whereas until recently he would just lay down and look at us pleadingly to take them away!
We did lots of research (there are some well balanced old discussion threads on the subject on here) and our personal conculsion is that castration will eliminate/reduce the risk of some nasties but castrated dogs are then susceptible to other nasties anyway.
So our choice has been that Roly ain't broke so don't need fixing!
However, if health or behaviour reasons as time goes on necessitate castration then we won't hold back from doing what is best for Roly.
Good luck with your decision - I am sure you will find the best way ahead for you and Oliver