I don't have an answer... that is why this topic is interesting. I assume folks here are big Home Automation users so they face the same issues I do but maybe that is an incorrect assumption.
I have about 200 reserved IP addresses in my router (a Peplink Balance One) with maybe 170 devices online at any given time with a 50/50 split between wired and wireless clients.
I am surprised at the suggestion that you do not need to reserve addresses or that the router should not handle DHCP. With my router the DHCP table is what links the mac address to a device name and lets you group similiar devices into a specific IP range. I cannot picture troubleshooting my environment without this.
I am also surprised folks don't consider dual WAN important. I guess I have never lived anyplace where ISPs were so reliable that you don't need a backup; especially if you also work from home in addition to regular Home Automation and entertainment consumption.
I am a little surprised that many Home Automation folks would use a single router instead of multiple access points. Even if you can cover your whole house from a single location, the number of wireless connections trying to talk to a single device would make it suboptimal.
I am also suprised there is not more concern about Sonos and other troublesome/special requirements type devices that are typical in HA environments, not only for entertainment but also commonly as the easiest path to TTS for platforms like Hubitat, Homeseer, and Home Assistant.
I am not looking to challenge any of the views here but rather trying to learn new things which I might be able to apply to my own situation so I am interested to see what solution the OP ends up with.