I caught this over the weekend and on the whole thought it was a good production. Mostly, Culkin was a revelation. It was the first time I've seen him on stage, and clearly his experience showed as he was a natural up there. His performance felt lived-in, honest, and I thought he earned every moment. Cera was a little hit-and-miss for me, but more hit than miss. Especially given his character, written to be an oddball and uncomfortable in the skin he lives in, Cera used his persona and any stage-jitters to good effect (or at least his casting was effective in the part.)
Gevinson was the weak link, by far. Almost her entire performance felt like an actress concentrating more on projecting for the Balcony than performing a character. She had some moments here and there, but the dominant note of her mostly one-note performance was "enunciate and project loudly." A stark contrast with someone like Culkin, who was as clearly-heard without sounding once like he was projecting beyond reason.
Words don't deserve that kind of malarkey. They're innocent, neutral, precise, standing for this, describing that, meaning the other, so if you look after them you can build bridges across incomprehension and chaos. But when they get their corners knocked off, they're no good anymore…I don't think writers are sacred, but words are. They deserve respect. If you get the right ones in the right order, you can nudge the world a little.