I’ve never tried using Ignition behind a reverse proxy. Typically a port forward from your router to your Ignition gateway in a DMZ would be sufficient. I suspect that you may be able to gain marginal security benefits from that approach. I can’t think of any performance benefits (caching, load balancing, etc) that would come with a reverse proxy.
What is the motivation behind this? Are you using SSL? My guess is that your Ignition gateway may necessarily be on the same network segment as sensitive nodes (either control or business). Even then, port forwarding with a firewall in between may be approximately equivalent. A lot depends on your architecture and requirements.