Well @ymerj, you may not be that impressed with the proof of concept, but I don't picture myself being able to spend a day poking around and put something together that works. This would be a really nice integration to have, but if I really look at the core reason I wanted something like this, it isn't just to bring HA compatible devices into HE, it is so we could use their HomeKit Controller integration. So if we actually had an integration exactly like HomeKit Controller on HE, then we wouldn't need an HA > HE only integration because, not only would we be able to get everything that HA has into HE, but virtually any hub or device out there.
Can you think of devices and hubs that cannot either directly connect through HomeKit or connect to Homebridge via a plug-in? I can think of a few, but the list is very short. And a HomeKit Controller integration like the one HA has wouldn't require that anyone have an iOS or Mac to accomplish bringing just about anything into HE. They wouldn't even need to run HA if they didn't want to.
