Pass on Wheeler Springs Campground (CA33 near Ojai) if is it warm to hot. The bugs will be vicious and beyond persistent. That is probably true of most of the CA coastal mountains. Out of bug season it can be an enchanting place. Nice little creek runs right thru the campground. It can be full all week during peak camping season.
McGill Campground west of Frazier Park is fairly high in elevation and good for summer trips. Haven't been there during bug season, but they being unpleasant wouldn't surprise me. An unusual consideration is the mountain bike trail that cuts thru the campground. Choose your site with this in mind.
Carrizo Plain has two designated campgrounds, KCL and Selby. KCL is the only one worth trying for. Selby is literally a gravel parking lot on the side of a hill. Not a summer destination with kids. Will be hot and miserable. The southern entrance off CA166 is dirt and varying wash-board for most of its length. The route in from the East over Hurricane Ridge will test your
brakes severely between the ridgeline (stunning view!!) and the floor of the plain. Choose this route with care, I wouldn't tow a travel trailer of any size over it.
Emma Wood Parkway is literally on the side of Hwy 1, and on the opposite side from the RR tracks. That said, the other side of the camp spots is immediately rip-rap & beach. The more northern end has wider sites than the southern ~70% of the sites.
Note that there are also two sections of Emma Wood State Beach. The section closest to
Ventura is tent camping only. The section further north is for RV's and is actually on the original coast route pavement. Surfer's call this small coastal point "Overhead" because of the Hwy1 bridge over the RR tracks. When there is a good break happening they can be quite numerous. Adjacent to the beach near the tent camping area are the remains of two WWII coastal battery's. The central pivot and a circular concrete ring with a circular rail is all that is left of these gun emplacements. Last I was there one of them had mostly succumbed to the ocean.
There are two
Ventura County Parks with overnight stay along the Rincon. Faria Beach Park and Hobson. Both have snack bars of some sort. They're popular and I'm not up on what it takes to get into them. They are a little more removed from the hwy. This section of Hwy 1 doesn't see the kind of traffic that the Malibu section does, not with 101 just a little further over, but it's not traffic-free either.
Calico Ghost Town campground (San Bern. County Park) has showers in the upper loops, don't know about the lower, OHV area. Spring and
Fall are the best times of the year, but I've experienced pleasant if cool weather there in January. I've also experienced brutal cold and on a different trip almost brutal hot there in mid April. Can easily hike into some interesting canyons from the Eastern Upper loop. The park rangers will keep you from entering Wall St. canyon at the upper end of the Ghost Town's lower parking lot because of flash flood concerns, but the canyon is very pretty. Depending on the route it could be a longish hike to see it from the top of the Falls, but very worthwhile.
As an aside, if the budget allows and there's room for it might look up the "Clam" bug shelters on Amazon. We carry a 4 sided version with the added sidewalls for a shower room and a friend with 'tweener' kids uses a 6 sided version with sidewalls as their sole tent on rough Off-highway trips.