^^ This is a v. good route, nice to fit in Yosemite etc. I'm a big fan of leaving late in the evenings particularly where the scenery is so-so.
One thing I like about SB->PS is that it is usually a good drive for traffic, so long as you time it so you stay out of peak hours - it can be slow from the 101-405 junction to the downtown LA exit (can't remember which) but then it's pretty smooth all through Pasadena, San Bernadino etc. Usually takes me 3.5 hours door to door with a brief coffee/gas/restroom stop
SLO - if you are getting there in the evening, you can have brunch the next morning and get going, no need to spend a whole day/night there. Add in a stop at Monterey/Carmel instead.
I would take on board the suggestions for doing LA/Universal towards the end of the trip rather than the start.
Here's my suggestion - basically the above with a couple of minor tweaks.
Day 1 - Arrive LA - Go to Santa Monica for the afternoon/evening. Alternatively just leave the LA area and head north on PCH (2hrs) - if you get in late, have an evening in Santa Monica, stay there, then leave early and drive PCH in the morning, stop around Malibu for breakfast/brunch. If you arrive in LA in the morning or up to say, 2pm, grab brunch/lunch in SM, then take PCH up to SB.
Day 2 - Santa Barbara
Day 3 - Santa Barbara
Day 4 - Santa Barbara - leave late afternoon and drive up to SLO (1.5 hr drive)
Day 5 - Breakfast/Brunch in SLO then up PCH to Monterey/Carmel (it's actually only a 3hr drive, but plan for at least 6-8hours for stops and detours).
Day 6 - Day in Monterey/Carmel - leave late afternoon and drive to SF (2 hr drive)
Day 7 - San Fran
Day 8 - San Fran (leave late, stay in Modesto) (1.5 hr drive)
Day 9 - Yosemite (Leave early! 2 hr drive)
Day 10 - Sequoia (aim to arrive late in Bakersfield) (3hr drive but v. easy)
Day 11 - Palm Springs (3.5 hr drive - leave early!)
Day 12 - Palm Springs -> San Diego (2hr 45 mins - leave late afternoon!)
Day 13 - San Diego
Day 14 - San Diego
Day 15 - San Diego -> L.A. (check out Encinitas on the way, cool town) - I like Studio City as a place to stay. It's close to Universal and a short hop over the hill to Hollywood/Beverly Hills to check out on the way to the airport if you have time.
Day 16 - LA (Universal)
Day 17 - Fly Away
So essentially
LA/SB (3 nights)
SLO (1 night)
Monterey/Carmel (1 night)
San Fran (2 nights)
Modesto (1 night)
Yosemite (1 night)
Bakersfield (1 night)
Palm Springs (1 night)
San Diego (3 nights)
LA (2 nights).
Depending on what time you get in on Day 1, if you can get to SB at a reasonable time (like before 9pm) then you could drop one night in SB and add in a night in San Fran. Or could add a day/night in Santa Cruz on the way up to SF, or add a stop in Temecula on the route from Palm Springs to SD. Both are pretty much on the way with only a minor detour.