Hey, Alina. Since you mention the Getty Villa, there may be another possibility very close to that one. This would be for Crawl #15. The Lake Shrine at the Self Realization Fellowship, on Sunset near PCH. Of course, it is a religious place, but it's all-inclusive of different religions and you don't have to be a religious person to enjoy it, either. It's just a really pretty place with an abundance of things for us to sketch.
Here's a wiki article on the place: http://en.wikipedia.org/wiki/Self-Reali ... ake_Shrine
I still have not been to the Getty Villa, but I think you have to make a reservation at least a week in advance and I don't know if they have a limit to the number of people, but I'd guess probably so.