Hello Derelict.
Sorry for the delay of my response as I promised to comeback and advise if it works or not.
I applied your rules on a fresh pfSense install and started testing. The PC had Internet until I applied the FROM_VSAT and TO_VSAT to WLAN out traffic. After setting up the in/out settings, I was able to resolve, ping and traceroute to the host, but could not browse the page itself.
What I did was to add a rule in Firewall>Rules>LAN with the following:
Action: Pass
Interface: LAN
Address Family: IPv4 (we do not use IPv6 in the company)
Protocol: any
Source: any
Destination: any
Description: LAN ANY TO ANY
In/Out: To_VSAT / From_VSAT
Saved the rule, moved it to the top, applied the settings and after that all works like a charm. Incoming connections are limited to the speed and latency setup in limiters for both directions but at the same time any LAN traffic is unlimited so a ping from the LAN Net to LAN Net is not affected. I find it useful to have an option to apply the limiters to the LAN network as well for some tests, where in production environment a need to troubleshoot a slow network/latency is needed.
I am extremely grateful to your help and I hope that this short tutorial plus your extensive instructions would be useful for others who need to emulate VSAT or just any other bandwidth, latency, package drop etc. limitations. The options are limitless and it is up to us to see how can we use it.