Help chosing the right gateway

Hi everyone. I have tried looking through the Unifi webpage and use Chatgpt to get closer to an answer but I am still in doubt.

This is for my home - I have a NAS & Home server in a rack and a router from my ISP. The level of control in the ISP router is to scarse and I want to buy a gateway from Unifi. I already have 3 access points throughout the house, and three routers from Unifi. In my server rack I have a Unifi 16 port switch for security cameras, home servers etc. My goal is to setup different VLAN's for IOT devices etc. and to make use of the Firewall & Intrusion Prevention (IPS/IDS). Even being in better control of my DHCP and NAT rules.

I am running the Unifi Controller on my home server for now, so no hard requirement for a solution where that is part of the gateway. As I have the switch I don't need a lot of ports either. I have access points in place so no integrated Wifi needed. I would like to rack mount it but it is not a hard requirement - I can go for one of the compact models if it makes sense.

The ISP is provding 1000/100 Mbit, Coax but fiber is going in to ground as we speak so I can expect faster speeds in the future.

What would you suggest?