Orlando cuts to the quick of Woolf's life as much as any of her work. Like you said about the tongue and cheek humor, it is one her more personal books. What I liked about the humor of it is how this destroys the Conventional Wisdom that surrounds Woolf.
In most reading circles that have read little of Virginiag Woolf's work there is a belief that she was nothing more than dark and brooding. To the Lighthouse, Mrs. Dalloway, and Jacob's Room all deal with hevavy emotions and brutal realities. If this is all you read of Woolf and only know that she commited suicide to are bound to see her as a dark creature. Buit with Orlando we are privy to something that she seemed to keep even more private than her saddness, that is her happiness and humor.