Another good slaw is that sold at the El Pollo Loco chicken chain here on the West Coast.
It's always freshly made, crisp and with a minimal mayo-based dressing.
Although I'm a fan of their chicken as well, I'll many time just order the slaw to go and serve it with something else I'm preparing.
I know everybody's taste varies widely but the biggest turnoff for me with slaw is sweetness. I like the dressing to be heavy on the vinegar and mayo but very, very light on sweetness.