Yes the Apple HomeKit platform "could" be very very good. I have been a Smart home hobbiest for 15 years and I feel this has the real potential to be an excellent platform (one of the best). The problem is apple is so slow at fixing/addressing issues. I can't think of any smart home user who will wait an entire year for a fix for issues and/or features. I was hoping that the last 10.3.x release would add something new...apart from a new hardware module.
My seasoned advice is do nothing...purchase NOTHING apart from a couple of test units until the software develops...its the software that will kill this before its even started. The current hardware out there (whilst not extensive) is really good quality and works well.
Come on Apple..everyone else now is running rings around you.