As much as I love the Coast Road and the Big Sur area, other than Highway 1 there just aren't that many other roads for our drives. While driving to Big Sur vs. Tahoe is similar for me, many of those who have attended in the past three years we've been doing this have driven out from Oregon, Nevada, and Arizona. Big Sur vs. Tahoe is a big difference for many of them.
If we were to consider the Coast, I think further south than Big Sur, maybe near San Luis Obispo or Pismo Beach might make more sense. Sycamore Hot Springs Resort in San Luis Obispo, (really just an old hotel with hot spring tubs in each room and a group of hot tubs along a path up a hill) is very nice if we could get a group discount. We could do one day on the Coast Road, and one day inland.
Of course we could do one day north (Honey Lake/Lake Davis area) and one day south (89 to 88) in the Tahoe Area.
Other geographical suggestions?
Bill