...and noting that you're driving north to south rather than the south to north I mistakenly thought in my initial response, then I'd suggest that you send two nights in the Monterey/Carmel area. There's an awful lot to see there. In addition to those already discussed, there's Cannery Row (if you're a John Steinbeck fan), docent-led walking tours of historic Monterey, Point Lobos State Reserve, and possibly a drive over to Pinnacles National Monument using Carmel Valley Road (County Rd G-16).

AzBuck