The US based cycling club I know has different levels of rides based on average miles per hour - Group A averages 20 mph+ and Group B averages 18 - 20mph. Though, doubtful that we are large enough for that as example- though that is generally a flat road average.

I would like to do Group rides as well but again don't want to slow anyone down. I love going uphill compared to flat rides but at 84 kilos I am not really a natural climber.

Zurich Oberalp is where I ride 4 to days out of 7 in the summer. Weekends I try to get into the actual mountains. My main training rides last summer for the Maraton Dolomites and the L Etappe consisted of trips up the Pfannenstiel, rinse, repeat, rinse, repeat, etc.