Router Advice - Modem Mode?

I would be reluctant to say one Router will work.  Personally I would suggest two or three WIFI access points set around the property to distribute the signal.  I use a non wifi router and 3 PoE ceiling mounted AP’s for WIFI.

Is your Virgin router the Hub 5 or Hub 5x? If it's the 5x, it doesn't have a working modem only mode but there are workarounds. 

I use a similar setup and I’m very reluctant to advise people on network equipment unless I’ve tested it out myself. That said, I run business class equipment that is probably too expensive for most users. I have 2 ISP connections, VM 1G plan and 1G symmetrical fibre from Open Infra.

Hard-core gamers will always get better performance with ethernet connections.  Can you run ethernet cables for them? 

Stick to a full network cable solution for Gamesters. 
Wi-Fi is always the source of endless Gamester grips about latency & for good reasons.

Many options to go with I use Zyxel firewall but your likely only needing a simple home router maybe some AP.

So on the low end your looking at something like this.

TP-Link Archer BE230 Dual-Band WiFi 7 Router, 3600Mbps Lightning-Fast Speeds, 2x 2.5G WAN/LAN and 3x 1Gbps LAN Ports, USB 3.0 Port, VPN WiFi Router, HomeShield Security, Easy Setup, EasyMesh : Amazon.co.uk: Computers & Accessories