Looks interesting! Any idea of price?
Having created my own doorbell system (ESP32-based, of course) because I am deaf and none of the existing solutions worked for me, could I make the following suggestions:
* Allow for more than one front end (that is, the bellpush). Front door, back door, gate on the drive, etc.
* Make available (or have an API for someone else to make available) a PC app that sits in the background and pops up (and flashes so it's hard to miss) when the doorbell is pressed. For your system a video image (or even still) would be great, but just the notification would be good.
* Allow for more than one smart chime and display.
With multiple sources the displays/chimes/apps would need to show which was the trigger. For instance, with mine the PC app and remote flashers (which are small boxes with a BIG light dome that flashes) have configurable colours depending on source. The PC app, of course, also says which source it was: "Front door", "Office", etc.
Also, with multiple receivers, it's useful for the receiver to be able to tell the system that the visitor is being dealt with. Without any response, the entire thing times out after 30 seconds assuming that there is no-one around, but that's quite a while for the apps and flashers and sounders to be doing their thing, and someone on the loo might be rushing to, er, finish while whoever was in the kitchen has actually already dealt with the visitor. So the responder can press a button on the flashers, or click on the app, and that signals all the other devices that someone is responding, thus relieving (sorry!) the person on the loo from rushing for no reason.
And... since it's all network based, the receivers periodically poll the bellpushes to verify that they are alive (and/or the network is networking). If anything drops out then the users are notified via a very low-level indication of the issue.