Not familiar with your hardware but if your Asus router can handle VLANs in AP mode you should be good. I am sure others have more experience with this…its likely good for a single WLAN.
You have a Managed switch which can handle VLANs (although some have expressed concern with TPlink...I am sure it is fine!)
As mentioned it looks like your pfbox works...nice RAM(32G)!
The Unifi AP is well regarded and super easy to setup for VLANs. Again find out if your ASUS supports VLANs before spending the $100.
Not a huge value in GeoBlocking I also share the same concern...TOR, VPN, hijacked PC are likely the hackers route. I only suggested getting IPv4 and GeoBlocking as a way to get started with pfBlockerNG. The real prize, I found is with DNSBL in the blocking of ads but it requires you to make sure your DNS Resolver is set specifically.
Make sure you can navigate to the DNSBL Virtual IP...if not it won't work. Also go to the alerts tab and see if you get an alert after navigating to the DNSBL Virtual IP....