We just got back from a very similar trip to LA for the same reasons as you and visited those schools and a couple more. My advice is stay at the best place you want where you can do something before or after your school tours/visits.

In Santa B, we stayed at the Double Tree Fess Parker. Not the newest but in a great location across from the Pacific. We also stayed at the FS Wilshire in BH with Perks from the FHR program from AMX. Happen to be there during the Jackson thing at the hotel and that was pretty cool. UCLA is right around the corner.

We saw a class on the beach UC Santa Barbara which was pretty cool and get your ankles in shape for the steps at Pepperdine. Don't miss the cafeteria or Chapel.

We were blessed we had minimal traffic the whole trip. The main thing you need is a Great GPS that you know how to use. I've been a big fan of Neverlost from Hertz for years. We even made it to Laguna over 100 miles south from Santa B the night before we returned from LAX. It was so chilly in the evening we had Hot Cocoa in July!

Lots of Perks and Deals out there if you take time to find them. Free night at FS Wilshire and kids up to 18 eat all meals free at Fess Parker.

My Girl is leaning toward UCLA but we have a couple of years to decide.
While in Santa B, don't miss State Street shops.

Nice to see someone from MCO out there, that's our home as well.... MCO was 100 plus degrees while LAX was about 72. CA is great this time of year but it's always a long trip back to MCO and no 767's.