There is a new (to me) commercial remoting protocol named Nice DCV. If using Amazon's AWS for hosting your graphical workstation, Nice DCV is free... but if you want to run it on your on-premise physical or virtual system, it requires a commercial license. Supposedly Nice DCV is very performant and is being used for cloud hosted graphics workstations used by artists working for CGI production companies.
I've not used AWS before but now I'm going to have to look into it. I don't expect a graphical workstation VM in AWS to be cheap but I definitely would like to try it out to see how well it works... and I'm once I learn more about it, I'd like to see how much the commercial Nice DCV costs.
The RHEL podcasting folks have a nice presentation showing this stuff and explaining how RHEL (and clones) are great OS choices for remote workstations.