I believe this is a cosmetic thing, for most dogs that have come to be recognized to look a certain way. I know that all the rotts I have ever had or worked with had their tails docked, but as puppies when they were 3 days old.
I think it is not completely necessary,I think it is like plastic surgery in some people, they want a certain "look" and can only attain it through surgery.
As for the neutering.............. except for conformation I don`t believe that there is any downside to it. I do think that a lot of people will wait until the dog is older so that they reach their optimun growth, however, I found that some people like the "bitchy face" a male can have if he is neutered early. The male rotts I worked with were a mixed bag of looks. The ones that were neutered before a year tended to be somewhat smaller but had the most gorgeous faces.......... more like a female head............than the ones that had been neutered after a year old. The males that had been neutered after a year had a more jowely look to them.
Since he is going to be a pet there is no reason not to neuter him, and when you decide to do it, it is basically up to you.
I think they are gorgeous dogs with or without tails. Because he is a rotti you won`t have to worry about whether he is aggressive or not for a reason for people to think twice about just sauntering into your yard, their presence alone makes people think twice. Too bad most people don`t realize that they are the biggest sucky babies!
In my experience with the rotties I knew, the only ones that showed any aggression were the ones that had been mistreated, and those ones had a good reason to be aggressive and not trust humans. They were all rehabilitated, even though some took a LONG LONG TIME.
My suggestion for you is to read a LOT about them and to ask LavenderRott about what you can expect for temperment and training. They do seem to go through a few periods in their development where they will try to "test" you and win alpha dog position. Like all dogs I think teaching them manners and obedience is extremely important. I despise dogs that have no manners................ no matter what breed they are.
Good luck with the puppy and kudos for you for handling the situation at the vet the way you did.......... nice to see someone stating actual "facts" in defense of their decision.