I'm more biased towards #3 and like the mimic of In Living Color's style. But the taller, laughing "Y" in #4 should also be in #3. If you could incorporate a littttle more flourish other than text, that would be helpful. A splash of a line perhaps. Tilt the words slightly. Something to make it a little more off kilter. Great start!
Client is asking if there's a way to highlight the abbreviation WTF more, so we still see the words What the Funny, but WTF stands out. That way, people see WTF first, but it reveals that the F actually stands for Funny.