Don’t focus on HA integration, just focus on getting a router that provides good coverage and speed reliably. You don’t want a router that causes wifi disconnect issues or a weak 2.4ghz network. I have an old Netgear R7000 and a T-Mobile (ASUS) AC1900 router, and both have issues running guest network and having over 20 devices connected. I’m currently using a TP-Link Onhub and Google Wifi running as mesh, and though the max wireless speed is low, it has been reliable so far.
Some routers may have HA components, but you will need to look into detail to see what it actually supports. Google Wifi has a component, but it just reports firmware version, uptime, and other unimportant info. If you want a router that HA can use to scan for devices connected to wi-fi, I would look into alternative methods like using the ping sensor. I tried using the Netgear component and didn’t find it useful.
I use two Amplifi HD routers at my friend’s house–they are connected via wired backhaul. I have Smartthings and HA set up there and everything works fine but there are only a dozen devices connected to the network, so it’s not being stressed. The Amplifi HD router has been out for some time…I don’t expect HA to create a component for it, unless there is an API available. You can’t access Amplifi settings via web browser, only by mobile app, unless something has changed in the past 8 months.
So, there’s nothing wrong with Amplifi HD, though it is getting old, it’s not the fastest and doesn’t have many features. Setup and maintenance is easy to use with the app, though Google Wifi excels in this area. It does have 4 LAN ports built-in, which may be important for you. Be aware that if you buy the bundle with the mesh points, the mesh points are hard-coded to work only with that bundled router. So if you plan to resell the points or pair it with another router, it won’t work unless tech support fixes it for you.
I currently recommend Google Wifi, but it’s not for everyone. It is slower (AC1200 for the pucks vs. Amplifi’s AC1750), only has one LAN port per device, and can’t use the guest network the way I want, but it has been stable with 30+ devices on the network, constantly streaming multi-room audio or video. The mobile app is also great, and there are frequent updates to improve security and add features. I’m hoping this is the router where I never have to reboot, or worry that a firmware update will break things.
If you worry about security vulnerabilities of your network devices, you will need to research routers that support VLANs. The Amplifi HD and Google Wifi support guest networks but no VLANs. The other Ubiquiti products should support VLAN, but expect to spend a lot of time managing your network with those devices.