Pickin’s have been relatively slim for Nicia Carla over the past year or so — Snail in A Year With Frog & Toad, hookah-puffing Caterpillar and a Tweedle in Alice in Concert, the pirate Starkey in Peter Pan, and the insouciant Grace Bradley in Best Christmas Pageant Ever. Yet the diva of ImaginOn has brought her own special sparkle to even the smallest of these roles — and glimmers of distinction to that turkey Alice. We don’t see enough Nicia onstage at Children’s Theatre, probably because she’s proven so adept at directing, treating us all to fine productions of A Thousand Cranes and Secret Life of Girls over the past two seasons.