If you don’t get any other answers:
I run OpenWRT on my router (x86 hardware), and have Adguard Home and Wireguard installed on it.
AdGuard has its own webUI, and Wireguard peers can be managed through LuCI in OpenWRT. It also supports OpenVPN as well as other VPN types.
So you could run a VM with OpenWRT and get all that.
Can’t speak for OP, but the Vault software itself is fine. It’s their recent change in licensing that has a lot of people upset and looking for alternatives:
https://www.hashicorp.com/blog/hashicorp-adopts-business-source-license