I have yet to get a yarn from knit picks that I don't like. I prefer super wash wool and adore Felici sock yarn.
I'm also a fan of CotLin, Dishie, and for felted wool slippers, Wool of the Andes Bulky.
Their Shadow Tonal lace weights are scrumptious, as is the Imagination sock yarn. Brava bulky (the only acrylic of theirs that I tried) knit up nicely.
And what's a yarn diet, other than a steady accumulation of fiber yumminess?
Those who think it means going without yarn, please say it isn't so...