Re: My first build. Need some advice and I have some questions.
Welcome aboard. Don't worry that your post was lengthy. We like posts that contain plenty of precise info, for that matter. You did just fine on that.
The bike you've described will be fine. There's no doubt about that. But I'm also wondering if you might be better off starting with something more modest.
Your riding conditions sound almost ideal. The only downside I can think of is that you're likely to be dealing with a lot of stops and starts if you'll be riding entirely on residential streets. So you might want to go with a larger than normal drive sprocket. Or roller, if you go friction drive. To get the most low speed torque.
The bike you described above will likely be plenty up to the task you're describing. I'm only a bit concerned that you might spend $1200 or so only to find that the bike doesn't quite please you. If you find that you don't like, for instance, your stance then that might be enough to make the bike not good enough.
So why don't you consider doing a $400 build? Maybe a china girl engine and 48 or 50 tooth drive sprocket. Maybe a friction drive. They both ought to be able to handle a Phoenix residential commute. You'll get practiced at keeping these things up and running. Then when the day comes that you want something higher-grade, you'll have more experience. Then you'll likely know exactly what you want.