I love the pittie square heads too. Luc's head it's that boxy but he's still pittie enough for me. IHe's on the lean side, for sure. He's way too friendly and happy-go-lucky to be intimidating to anyone.Ooh they do look alike! I'm hoping he gets a big boxy head and jowls, somethin scary so that people don't want to come into my yard.
I probably won't even fix him
I know lots of people will probably hate me for that one. But I don't want him to breed, I just want him to grow properly, and intact Males are also more confident.

Not getting him neutered is a bad idea. It's good to wait until he is 6 months so major growing is done but after that he should be fixed. Any perceived benefits are far outweighed by the risks, such as the average shorter lifespan of dogs that aren't fixed. You might not plan to breed him but if he gets a whiff of a female in heat he'll be gone. I believe confidence will be more dependent on personality and training. A dog that is exposed to a lot of new things and people at a young age is more likely to be confident, for example. Not going to give you any hate, but you should really think it over. Luckly, you have lots of time.