You should add a day in San Diego to your itinerary.SF - LA - SD - LVSan Diego is only an hour and half from LA and there are lots to do and see there. http://www.socalthemeparks.com/Grand Canyon is not that close to Vegas but there is the Hoover Dam which is 45 mins from Vegas.http://www.lasvegas-how-to.com/las-vegas��
Be sure and drive down the coast instead of on the freeways. Monterrey is quite beautfiul.