So, I have two recommendations for you, one is local to the Bay Area and one isn't.
Erin Medina: https://www.theeroticreview.com/reviews/erin-medina-361389
She's based in the Bay Area and even though she's under 30, she's an amazing companion. She has impeccable taste, is classy and refined, has an amazing sense of humor and is well versed in a number of different ways. If you view her TER profile, send her email to request the URL of her personal website where you can learn more about her. I've seen Ms Medina a few times now and have always enjoyed her company.
Grace Harlow: She's not based in the Bay Area but visits the area frequently, close to once a month. I've seen her several times now and she's amazing. *Very* slender and toned, yet *very* laid back and easy to get along with. Like Ms Medina, Ms Harlow has impeccable taste and so on. Ms Harlow is also not yet in her 30s, but I still recommend her with absolute confidence.
Both ladies also have a great sense of fashion, even though Ms Harlow tends to prefer the color black. If you search Tryst for her name, you can find her ad and a link to her personal website. Both ladies would make amazing dates for dinner, a show or some other adventure.
Last but not least, Ms Kate LaFleur: https://www.theeroticreview.com/reviews/kate-lafleur-374147
Yes, I know I keep mentioning her but she truly is an amazing woman.

I haven't seen her as often as I've seen Ms Medina and Ms Harlow, but each time I have seen her, she's always well dressed and overall presents herself in a very classy, upscale fashion. Ms LaFleur certainly is in the age range you specified.
I was going to recommend one other lady, but she's not really taking on new clients right now. If that changes, I'll post her info in this thread.
Hope this helps!