I prefer Pirandello's _Six Characters in Search of an Author_.
I like that, too, and my all-time favorite is Henry IV. But I do love it when the husband, having set his ex-wife's lover up, says, "I told you, Guido, I do know the rules of the game."
I remember seeing a production of Henry IV with Rex Harrison in L.A. many, many years ago (1973?). Unfortunately, I had been sleep deprived for several days before the performance, and--shame, shame, shame--I fell asleep and missed much of the performance. There is perhaps an irony there that Pirandello might have appreciated (though I suspect Harrison would not have been amused).
Harrison, who thought extremely well of himself, would definitely not have been amused.