Fitting everything in two front rollers plus tent on rack doesn't require much of anything special. I managed that kind of volume before I was even packing what I really consider ultralight without making any special effort at going compact. I think I hit that kind of volume around the time my base weight hit 22 pounds or so. I am about half that base weight these days.
I find that I can manage less volume that that these days without specifically trying to reduce volume for volumes sake. I do use a Borah side zip bivy (or sometimes a bug bivy) and a light tarp and my sleeping bag packs about softball sized. Clothing is carefully selected and it all packs in small stuff sacks where if compresses a good bit. My cooking/eating kit is varied with the trip, but they are all pretty compact.