I am reluctant to "teach grandma to suck eggs" if you can do setups in GPL why can you not in GTL or R3E
it's all the same concepts? I can tell you what I do, some is science, some is intuition, some is whatI "think" works
Well I thought the same when I started in GTL ( having been a GPL addict for many years), "Setups will be simples"
TBH I have not found it quite as easy as I expected and I have taken myself down some very dark tunnels searching for the magic solution. It feels to me like some parameters respond as I would expect them to in GPL, but others do not give me the same result.
Now, that might be because I am comparing a 67 Grand Prix car with a 1955 Maserati 5.7litre battering ram. If the physics are modelling the expected performance correctly, these cars are never going to behave in the same way.
It has taken me about a year of fiddling and experimenting, but I now have a basic "clive default" for most of the various car groups which I am refining with each outing. Practice time outside of actual races is limited for me at the moment so most learning and development takes place just prior to a race. Often I am wrestling with a less than perfect setup and hoping that the tyres will survive, but gradually that situation is improving.
Pitstops are an achilles heel for me and I might try and get that sorted in my head next.
The other issue is that both here and in GPL most people find my setups far too twitchy and "pointy", so maybe I am a little unconventional.
At the end of January I am officially retiring, but might return part time on various projects with my old company. Although one might hope that I will have more free time for important things like sim racing, the list of jobs my wife has prepared would make that dream unlikely!!