I was doing a bit of research for a future network overhaul (once money magically appears).. and ran across this pretty good article which talks about separation of devices into VLANs but still allowing discovery; this was a concern of mine in terms of segregation but sounds like it is pretty easy to overcome in the Unifi controller. Note this talks specifically about Chromecast and Home but, of course, would apply to any smart devices which rely on broadcast/multicast traffic to connect.
https://help.ubnt.com/hc/en-us/articles ... Fi-Network
Also, special shout out to @DaveL17 for forcing me down this path, for better or worse. Bill will be in the mail once equipment is purchased, Dave.
Adam