The immediate question is where do they live and will tours come there? If they live in or near a touring city, most musicals either already have or will play there. In the case of Billy Elliot it may not be soon.
Figure out what won't play there anytime soon or at all and go see those shows. Or in the case of South Pacific, it will play proscenium houses on tour but in NYC the show is staged on a thrust stage which adds to its immediacy.
Next To Normal, Hair (to a degree) and South Pacific are shows playing now that will be hard to duplicate in the larger road houses.
"If my life weren't funny, it would just be true. And that would be unacceptable."
--Carrie Fisher