The benefit is that you don't need to use port forwarding at all and you only need to have one port open. You can have HAproxy listen on the WAN on port 443 and send requests to the appropriate backend server based on the requested URL.
You don't have to remember what port the services are running on externally just the FQDN.
It isn't necessarily any more secure though. You only have one firewall rule on WAN so you can't apply different rules to each service at the firewall level. Connection limiting, traffic shaping etc.
You still can have HAprxy listen on different ports though if you found you needed that.

Steve

I moved the galaxy backend to the ssl offload fronted.

Added a custom ACL and used this https://stackoverflow.com/questions/23342036/haproxy-restrict-single-backend-by-ip-range

@jimp could you point me in the right direction how to setup so HAProxy on pfSense handels the certs ( not just getting them )

That was it, thank you for your help!

Probably not in this case.