You don't have to drive to get out of Santa Monica!!!!
Tons of teams go every year, and they just ride north on Ocean Ave and then north on PCH.
Tons of routes available, no car needed. San Vincente goes across the base of the mountains, with conenctions to Mandeville, Westridge, brentwood, lots of things that connect to Mulholland.
There's the LaGrange rides you can catch.
Plus tons of canyons off the PCH (Topanga to old Topanga etc).
Pretty much all around the Santa Monica mountains is accessible without driving.
If you don't mind driving... you can move off the Santa Monica mountains and there is Mt Baldy, Big Bear Lake, etc.
Use the strava global heatmap and you'll get the idea real quick.
http://labs.strava.com/heatmap/#11/-...9477/blue/bike