Yet another fantastic idea...
...that I want absolutely nothing to do with.
I can arrange to be in, I trust my neighbours, I certainly don't trust the random person who I never met who managed to get a rusty transit to skim through an MOT done by their mate and call themselves a delivery driver. If it needs to go in my house that desperately, my neighbour, who I know well and have known for years can put it in my house, and vice versa.
A porch is a reasonable solution, but not all buildings have space for that.
What I think would be a great idea would be to have public buildings, maybe an office of some kind, which have decent opening hours but with a secure area accessible only to staff. The delivery driver could put a ticket with a reference through the door and that relates to your package. They could even handle the post as well.
(Before anyone moans that they don't have a convenient local Post Office, or that it's never open, blame the unique way our postal service is now run. All the inefficiencies of a public run body and all the financial skimming and money grabbing of the worst kind of capitalism.)