All of us will have our own theories as to the best approach, so if we all chime in with the different ideas then you should have lots of ideas to see which fits you best, lol.
With my barky pup, I taught him "Quiet" and I also taught him that disobedience to that command was an automatic 10 minute time out in his crate. He really enjoyed barking at the neighbors until he was offered that choice, lol. I think barking is so much fun for them, and it is self-rewarding behavior - so they need to have an even bigger reward to motivate them to keep quiet. Like enjoying the sunshine while I garden, with a bone and a kiddie pool instead of the crate would be a great choice.
Getting people to ignore your pup is going to be the hardest training challenge, hands down. It was impossible to get one of my neighbors to stop talking to my pup while he was barking. That's where the flirt pole came in very handy, because that's his crack pipe, lol.