So… wow… this is great! Having just installed HA yesterday what I now realize is… I think I know just enough to really grind myself into the dirt. 
When I started I thought it had something to do with self-hosting and privacy. NOPE!
Where are the discussions on privacy? Should I give someone access to my github and go to sketchville to D/L files to crack my NSpanel ?. I did. I have a NABU subscription, I use duckduck for my searches. should I put a Google ai device in my home server? Feels like I am turning my chicken coup into a B&B for foxes.
Well I think a self hosted solution like HA is a good starting point.
Also, as highlighted in the post, use cyphered protocols, focus on FOSS, no Cloud dependencies as much as possible, no Alexa and other connected mics. Secure your remote accesses, segregate your networks. etc.
But there is indeed more to write on that front.