This thread illustrates the problem: people have different likes and dislikes when it comes to entertainment. We do find the "Broadway" type shows repetitive and usually now skip them.
The best entertainment I've seen has been from guest entertainers who come on board for a night or two, maybe give two performances, then rotate out. Doesn't matter if it is standup, magic, jazz, classical, even opera crossover. If they find a musician skilled in more than one genre, that's the best of all.(I realize they are likely budget busters, but the question was asked.)
I haven't found SB's lounge performers, like the OBS, very good lately. I just don't know the answer to this one.