VPN for entire house

I want to pass my entire house internet through VPN. I have a subscription to protonvpn which gives me very good speeds and allows for streaming services to pass nicely.

Now I have: 1GBPS Fibre modem from my internet supplier -> 32 port 1GBPS unmanaged switch -> Cat 6 to every room -> 3x Deco M5 for the mesh WiFi with ethernet backbone

My idea is to put a Nanopi between the modem and the unmanaged switch and use wireguard VPN to pass everything through it (wired and wireless).

• Although my internet supplier has a 1Gbps max, I only pay for 300Mbps. Never needed more.

• I cannot replace the modem with my own and it has proprietary software on board. Assume I cannot touch the modem.

• I tested my VPN supplier on my desktop through their app and it gets almost full speed (300Mbps). Also, Netflix plays nicely through it.

• In terms of equipment, I have my desktop, my NAS, my TV (Netflix, YouTube, etc.), 3 phones, 3 tablets, some IoT (airco, WiFi switches, home assistant running on a Pi 4B).

My questions: - Does it sound good to you? - Which NanoPi (don't need WiFi) - Anything I should be careful? - Other suggestions to do it better?