Just had my first taste of using OpenVPN/Wireguard running on OpenWrt on an old BT home hub HH5A. I've come across the well documented problem of download speeds (OpenVPN 10-15Mbs and Wireguard 35-40Mbs). Previously I was able to reach ethernet speeds of 70Mbs (Openvpn) with the stock UK ISP firmware.
My understanding is that there are some hardware limitations to HH5A. So can I connect an Archer C7/A7 or Netgear R7800 to act as the router to the existing BT hub (or and old BT modem Model B-Focus V-2) and reach the 70Mbs speeds with either OpenVPN or Wireguard? And would both require the Openwrt/unlocked firmware?
NB. I also have several wireless devices connected to 2.4/5Ghz bandwiths (speed not an issue for these).
Any advice or other router options would be much appreciated, thank you!