I've always wanted to do a cast like this, and I thought i'd change it up over on fan-fic. I don't know if Either Family Guy or American Dad! would translate well to the big-screen, but it's fun to think about and for one would love to see it. Keep in mind I didn't keep any of the original cast members cuz that wouldn't be fun or original.
American Dad!
Patrick Warburton is Stan Smith
Imo this dude is the perfect man for the job, I find Stan to be a dude who used to be supehero-like but now kinda let himself go, reminds me of Patrick.
Nicole Sullivan is Francine Smith
This was Ager's pick and it was a great one, she was funny as hell on MadTv, plus she looks just like Francine.
Clark Duke is Steve Smith
I think Clark's just right for Steve, he's good in kick-Ass and Hot Tub Time Machine, and plays similar characters.
Kat Dennings is Hayley Smith
Kat is hot, funny and I think she may well have been the inspiration for Hayley since she pretty much is her.
Niel Patrick Harris is Roger the Alien
Roger has kinda a 'gay'ish tint to his voice (no offence), but has a crazy attitude and Neil meets these criteria. He'd be perfect to voice.
Andy Samberg is Klaus
Andy needs more movie roles cuz the dude is hilarious, I can imagine him being really funny with his take on the exaggerated German voice.
Family Guy
Kevin James is Peter Griffin
Is this obvious as hell? Yep. But if James went all-out stupid for the role and maybe with the help of make-up to make him bigger, he'd be perfect
Mary-Louise Parker is Lois Griffin
Lois is a MILF, much Mary-Louise, who's sexy on Weeds and can play both the sweet and loving mother/wife, or kinky spontaneous side she gets ever so often.
Alison Pill is Meg Griffin
Meg's the kind of character that gets ragged on for being awkward and ugly, she's essentially the black sheep, and alison who you may know from Scott Pilgrim, can bring that perfectly.
Angus T. Jones is Chris Griffin
Angus is hilarious on Two and a Half Men, and he even kinda sounds like chris, and has the attitude down kinda too.
Malcolm McDowell is Stewie Griffin
So an old man to play a baby? I think it would just add to the humor of this mature acting, cynical baby, and Malcolm is frikkin' hilarious too.
Robert Downey Jr. is Brian Griffin
Brian's a smooth-type character, drinking his scotch and being philosophical every now and then, just the type of character hat Robert would excel at.
Bruce Campbell is Quagmire
Bruce has the chin to pull this off, and the attitude too, the dude's one of my favorite actors, and would completely own Quagmire.
Jon Hamm is Joe Swanson
Although Warburton is perfect ot be a live-action Joe like I said, it's no fun or original to use him, plus he is live-action Stan, so I offer up Hamm who has the same alpha-male attitude and looks that the paraplegic cop has.
Craig Robinson is Cleveland Brown
Craigs' an under-rated funny guy and would probably steal scenes as Cleveland can actually be really funny