The first choice is obviously former senator Al Franken. He's the only one I'd consider for president even without the comedy stipulation, so he's automatically #1 and honestly should be for everybody who wants to take a realistic crack at an answer.
But in a world where there isn't a really obvious and good choice, I'd approach that decision the way I'd approach any hypothetical where we pick a ridiculously unqualified person for president from a list that isn't known for producing politicians.
You have to look at things like intelligence, executive experience, political leadership, political participation, education, and political literacy first, imo (and not necessarily in any specific order). The job is so comprehensive and demanding that vetting them ideologically would have to come after filtering them for the ability to even do the job.
So I would look for entrepreneurs, producers, writers, or other people who do more than just perform, and who have accomplished things that require lots of intelligence and drive beyond what it takes to master their craft on stage. That gives you a dump of people who, off the top of my head, include folks like Chelsea Handler, Chris Rock, Jerry Seinfeld, Jay Leno, Larry David, Stephen Colbert, Lewis Black, Jon Stewart or Louis CK. I'm missing lots of people I'm sure, but you can see that some of those people might be good, and some of them would probably suck. Larry David, Stephen Colbert, Jon Stewart and Lewis Black are the ones I think would have an okay shot at being a good president out of that group, but that might not be accurate.
And out of those, I'd lean toward Lewis Black, because he is an excellent writer, incredibly intelligent, is politically literate without being fatally cynical (he's quite the driven optimist, which is revealed in his memoir), extremely hard-working, and a legit entrepreneur, though he's short on executive experience. He also seems like a pragmatist who is not too partisan, while also not being afraid to get in the mix with activism and protest.
And just to note, political satire is a double-edged sword. The good thing about it is that it demonstrates political literacy. Having lived through a couple of years of a politically (and civically) illiterate president, I'm not keen to repeat that mistake. The bad thing about it is that satirists can get by with being smart asses who are so cynical that you wouldn't want them near public office. Bill Maher would be a guy who is very politically literate and excellent at political satire, but who is way too cynical (along with other character flaws).
