No tuning lobbys with max 5% detune works for me. I've come across many GT5 shuffelers in these GT6 lobbys, so i'm basically racing with the same people as i did in GT5 shuffle.
PP limit is set according to wich track comes out of the vote, tyre limit changes according to PP limit CS for low PP to SH for higher PP races. Just like shuffle.
This works when te room is filled with GT5 shuffelers which usually is the case when i join these "friends" rooms.
In stead of picking only OP cars many guys pick just cool cars to race and have great battles with.
Its a lot of fun and makes for shuffle "like" close racing.
Just a clean room where everyone plays by the rules and show respect for each other makes for great racing, just like in GT5.
Edit: offcourse the room settings are realistic.
No boost
Depletion normal
Only ABS
Etc