How "small" of a cast are you looking for? Gender division? Subject matter restrictions? Vocal types?
OK, those questions out of the way, here are my first thoughts-
"Liars & Legends"- It's a musical-review-ish thing based on the story songs of Harry Chapin. About 4-6 cast members. I don't know much about it other than the songs are great (duh, considering the source), and I Like the script. I would LOVE to do this show. I think that it has a great chance to appeal to a baby boomer and younger audience. And there is so much that you could do with it.... I've been trying to convince the theatre I work for to do it, but no dice. Maybe you'll have better luck. (It's listed in the R&H catalogue).
"Two By Two"- (I've done this show before, so pardon the excessive description) Musical adaptation of the Noah's Ark story that shows the characters as people, rather than Biblical Figures. Danny Kaye was (I think) the original Noah. Quite funny, and GREAT music ("The Gitka Song" and "Goodbye, Old Girl" can still bring tears to my eyes, cynical bitch that I am, and "I Feel Like I'm Ninety Again" is SO much fun)
Cast size is about 8, evenly divided men/women. Great fun to do, fabulous music. There are (in my opinion) only 1 or 2 cast members who need "pretty" voices, the rest are more "sell the story" songs. One song can be cut to make a non-singing role. Most voices are character-type, or can be done so. However, if you live in an area with religious issues, there are some things that could be a problem. And the set could be problematic. Act 1 is at Noah's house as the ark is being built, Act 2 is in the ark, with water all around. And at the end, the ark lands and all disembark. It can be done simply, if your set designer is creative. And I think that, in this case, simple would be best.
Pardon me for rambling. Hope this helped.
"We are all misfits, I guess, in the theatre. Otherwise we wouldn't be here." ~Michael Kandel, "Ogre"