This is all good advice. The greater Temecula area is great, but it is quiet. Some fun wine tasting in the surrounding areas. If you want to feel like you went on vacation in California, you need to stay in Orange County. I live in Huntington Beach, have my entire life, so anywhere between here and San Clemente will feel like SoCal. I would recommend Huntington or Newport. They are not cheap places to stay, but they are beach communities with tons of local hot spots, dinning, shopping etc....
If I had an Aussie accent and was single on vacation, id be downtown HB or Newport a lot.... If you aren't motoing on a weekend, rent a beach cruiser and hit the boardwalk, given it is our "off season" (chilly 65 degrees at night) there is always life and things to see and do.
What would be epic, if you can swing it, is to stay somewhere around HB or Newport and rent a couple motorcycles to shuttle you back and forth to Temecula. The Ortega highway is a fun ride and very direct to that area. Its a ride, so I wouldn't recommend it tired, but if you are up for it, its pretty scenic.
If you are looking for restaurant or spot suggestions let me know, im happy to help, as I am sure many others are.
- When the Going Gets Weird, the Weird Turn Pro