If you consider Santa Cruz part of the Bay Area the Bonny Doon descent from Empire Grade was a blast (I haven't done it in 19 years--the pavement quality was very smooth then, but I don't know about now). I used to do a "big loop" from home a couple times a year through SaratogaGap/Big Basin/Jamison/Empire/Boony Doon/Highway 1/Western/Empire/Felton Empire/Zayante/Summit/Highway Nine/home and the BD descent was the highlight. If you're willing to drive to Santa Cruz, you could do a 27 mile or so loop that incorporates BD by starting at Western drive. (Also consider turning around at HW1 and climb BD to experience part of the Tour de California route.)