Assuming you are a responsible owner, so taking the accidental litters option out of the equation.
There is increasing evidence to suggest neutering, and particularly early neutering of larger breeds (under 2 years old) can cause more health problems than it prevents. Hormones contribute a lot to growth and health, in particular things like bone and ligament formation - I don't have the link to it right now but I was recently reading a study that looked at cruciate ligament problems and there did some to be a fairly strong link to neutering.
Early neutered dogs can also (sometimes) get stuck a bit in terms of emotional maturity as well.
Neutering isn't really a cure for humping - that's more to do with adolescent excitement, good training and your dog naturally maturing are just as likely to help.
I personally haven't neutered either of my male dogs, one of whom is now officially senior, and looking at him compared to neutered examples of the same breed, I'd say he looks in much better physical condition.
Each to their own though, only you can make that call, good luck whatever you decide