Can't. JG said the finale would let us say goodbye to all the characters and give closure.
There's no way they'd do the ultimate status quo now. Maybe before Season 4.
They've already set up too many things, like where Mordecai wants to go from the Park, will Rigby go to college, will Benson get back in a band (Mordecai and the Rigbys?) or at least find another job or retire, will Skips go back to being lonely or does he have a direction? He's been at the park since 1800, I don't think the park would be the same without the rest of the crew (in fact it could close) and he would have no one.
Everyone's going somewhere. Muscle Man and Starla might honeymoon or something but their character plots are over.