Los Angeles definitely does not have a shortage of comedy clubs, so my perfect suggestion for when you do not have any weekend plans is to see who is on stage at any of the countless comedy clubs in the LA area (improv or standup). Bonus, the shows are usually reasonably priced which can be hard to come across in Los Angeles for any weekend activity.
So, a few weekends ago when I did not have any plans lined up, I compared comedy shows around town and decided on Patton Oswalt and his standup show at Largo at the Coronet. Patton is a regular at the Largo, on average he does a show there once a month. His standup is of course entertaining, but his riffs based off of quick conversations with audience members make for such a great show. He is one of those naturally funny people who would be the greatest friend to always have at a party.
Largo at the Coronet has more of a theater setup, although all seating is assigned based on a first come first serve basis, as all attendees pay the same for tickets. There is no drink or food minimum, and if you are driving I suggest parking in the garage right next door. Based on the photos hanging from this comedy club’s walls so pretty great comedians have had shows at Largo, so I would suggest keeping an eye on their lineup in case one of your favorites stops by.