Recently, wait times have improved in many California DMV offices. Some of them have added Saturday hours, at least twice a month, and I think they have somehow accelerated service, perhaps by adding more people during busy times.
I'm not sure where OP lives, but you could get on Facebook in a local group and ask there which offices have short wait times. Another clue is the reservation system, where it seems that if there are appointments available soon (like two weeks out), wait times are shorter, and if appointments are being made 3 months out (!) the wait times might be longer.
I did a REAL ID renewal last May in Indio. I had an appointment, but there was no one in line anyway when I arrived at 9am, and I was out in 25 minutes. I also hear good things about Bishop, Hemet, Riverside East, and Palm Desert. AVOID Temecula! Driving 90 minutes to Indio and then back took less time than waiting in line would have. I think rural offices have fewer customers, so go to one if you'll be passing by on your way to your next timeshare anyway.
I don't believe you need an appointment, but be sure to bring all the documents listed on the website. Don't think "oh, this will be close enough," as it won't. They'll copy or scan everything and hand it back to you.
If DH has an appointment but you don't, you'll be made to stand in a different line, and he will finish long before you.
Finally, I believe they'll renew a license a few months (six?) early if you tell them you'll be out of the country during normal renewal time. You have to do this in person though (and of course you have to go in person for the REAL ID). Call 1-800-777-0133 and ask.