@Miller,
Cluster box units have been around for many years now - I used to specify them.
I'm not a big fan, but can see their utility. By now (I haven't seen such catalogs in twenty years) there may be some well designed ones.
Our delivery in my new area is contracted out by the post office, or so I heard.
It's not horrible, that I know of.
I am sorry if individual delivery full stops, as I've been strong acquaintances with three outstanding mailpeople. One guy used to make fun of me, until we talked it out and got to be pals about this and that..
But also, people in a housing tract can have disabilities that make it hard for them to get to the group mail box.
When I had moved away for some years but was visiting back in LA again, I needed to mail a humongous book to an architect up north, and went to a former local post office. There was a scream as I was filling out forms, STOP THAT WOMAN! (This was after 2001, I'm near sure, but maybe not). She probably didn't remember my exact name, but knew me with a quick look.
It was my old post deliverer, we had a great catchup talk there by the counter. No, not a counter with a line.