Independent components and progressive enhancement is the best way I can put it.
Like right now my HA system is complaining I've fucked up the DNS configuration somehow and this is stopping something??? working.
Also, LTS releases for HA and smaller, less frequent releases.
Monitoring built in to the system - it's running my house, it needs reliability, alerting and failover built in. It needs to act like building management appliance instead of a FOSS toy.