I saw the original production waaaaaaay back in my college days. To my mind, it's similar to "Oh, Calcutta" in that its main purpose was to expose "shock" as being not so shocking (specifically regarding sex and nudity). IMO, "Let My People Come" is a bit more intelligent in that it uses nudity and language to actually explore topics, rather than just pepper not-so-funny comedy sketches with gratuitous nudity.
My favorite number is "Dirty Words". The lyrics are shocking and bawdy, but the song then takes the extra step to ask, "why"?
I think the show is completely outdated now, but that's partly why I think it's worth seeing. It's interesting to consider how "scandalous" it was in its time, and to hear and see what the show was "preaching" at that time.
...and if nothing else, a little "titillation" is always fun.
John Forslund is a theatrical genius for reviving this! The space of the underground bar really gives the show a great vibe! The whole cast is terrific and they give a fresh and new feeling to it! It is currently one of my favorite shows on Off-B'way right now! I HIGHLY recommend this vibrant piece of theatre!