East Coaster Visiting San Diego - CH recs?

I'm planning on heading to San Diego to visit a friend at the end of October. Considering that the last time I've been to SD is at least 10 years ago, and all I remember is going to the zoo with my family, this time I plan on making it as CH-filled as possible.

Seafood, sushi, Mexican, new notable restaurants, random hole-in-the-wall places that have consistently good food... any sort of cuisine really would do. Price range- maybe one or two really "fancy" places, but otherwise we'd like to keep it maybe under $30 p/p. We will most likely be eating out most/if not all of the 5 days I'll be there, so any/all recommendations would be appreciated!! I apologize for not being too specific, but I'm really not a picky eater, and I love trying new places, and my friend has a car, so we're really up for anything! Thanks in advance for your help!!