DietPi / Fuzon

I don't know about Raspberry Pi vs VPN router. I set up a router for connecting to my VPN, therefore slow while connected to VPN. I also run VPN on my phone 24/7. My VPN allows 5 simultaneous connections with static IP address, so I am well within the limit.

Try Ivacy, it supports windows, linux, mac and android. Read the detailed analysis here:

https://vpnranks.com/ivacy-vpn-review/