Does this cause all traffic at the reverse proxy to appear to come from the source IP of your VPS or does it preserve the original source IP?
I've been working on setting up a similar setup myself and am trying to figure out specifically how to handle the forwarding on the VPS.
I'd certainly be interested in full details. This sounds like the best of all worlds of not needing to double reverse proxy, not hardcoding internal IPs in the config of a single reverse proxy on the VPS, and not losing the source IP.