First of all, I'm not sure where you're going to find cyclist homeowners who are willing to go to all that trouble.
Secondly, we have had threads here from time to time about the difficulties warmshowers or couchsurfing hosts experience with some cycletourists who are quite demanding. I know you're proposing that the cycletourist would pay, but still you're suggesting that the host have extra bicycles and a mini-shop in their house for the use of the cycletourist. To me, that just opens up the possibility of all sorts of difficulties. And the host would also be open to dropping everything and chauffeuring the cycletourist around if that's what the cycletourist needs? For one thing, not all cyclists have cars and/or have cars with bicycle racks ... and next, who has the time.
Thirdly, as soon as a homeowner starts charging for people to stay overnight, they have entered a world of permits, government regulations, insurance issues, etc. etc. I suspect warmshowers and couchsurfing get away with it because they are free services, and the cycletourist is staying the night like your brother or best friend would.
I've travelled a lot over a lot of years, but have never needed something like this. If I'm paying for a place to stay, I'll stay in a B&B, hotel, cabin, campground, or hostel ... where I can have privacy, peace and quiet, and be able to do my own thing. And when I travel, I bring my own tools.