You might find I10 to be a better route through Texas after San Antonio. The alternatives are not much better. Agree that the causeway may well need a miss. We rolled across with no delay, but there is no way off if a problem does develop and it is a long stretch of road.
You can take I20 to Birmingham, I22 to Tupelo, the Natchez Trace (very relaxing) to Natches, 84 into Texas far enough to head for Nacadoches (just sounds interesting), followed by Austin (hill country is great) and then San Antonio.
Note - The Long long honeymoon has a video on what to see in Birmingham.
You can get to Phoenix off of I10 by taking 70 out of Lordsburg. It is more interesting than the Interstate, but slower. The Apache Gold Casino is not a bad stay, but don't hit it on a weekend.
Do not miss Quartzite. It is not much and still a major element of the RV world.
San Diego is good and bad. It's interesting and there is a lot to do, but it puts you South of the challenging LA parking lot. If you are committed to Huntington Beach, grin and bear it. Just get in line and enjoy the ride. Play the reverse commute directions when possible.
Do the research on the Pacific Coast Highway. A stop at Hurst Castle can be a day trip from Paso Robles and it's worth the trouble. One thread that is running now.
http://www.airforums.com/forums/f42/...es-204363.html
Up 101 is Yanks RV Resort. I would not live there as it's too windy, but it is a very nice park and worth a visit. All concrete pull through pads. Well maintained. Your 33 will be right at home.
You will be passing Monterey on the way to Palo Alto. Might be worth doing the 17 mile drive. The views are fantastic.
In Palo Alto, you might try to fit in with the locals and students by parking on El Camino Real around the Stanford Campus area with all the other RVs. Not likely to find a spot open, so better to reserve a site within commute distance. The Park over in Pacifica is often recommended.
Salt Lake is a simple run up I80. There is a nice Passport America park in Winnemucca. The New Frontier Park is mostly gravel and a combination of pull through and back in sites. But it is new, clean and far enough from the Interstate to be quiet.
Note - the alternative to I80 is US50. The loneliest Highway in the US across Nevada and Utah is an interesting route and a bucket list for many RVers. Truly a different experience from I80. You have until Sacramento to chose your way.
Hope you have a good trip. Pat