I really hope they go with a sympathetic Galactus from the later stories. It's hard enough making a movie where the bad guy is an unstoppable force of nature (Dormammu, I've come to bargain) but if he's just another giant face in the sky looking to consume Earth, then it will be a missed opportunity. Closer to Ego and Thanos than Arishem. Obviously, he's not going to be charming and funny, but he could be hungry and conflicted about his role in the Universe. He could believe that Earth should have been destroyed with the birth of Tianut, and that Humanity had run its course. Maybe the gestating Tiamut was the only thing keeping him away?
I don't need to see the FF discover their powers again. Plus, the less time Reed Richards spends in the uncanny valley, the better. Galactus is a much more interesting character if they treat him like a character.
Totally agree with the broader point, but it won't be the arrival of Tiamut that draws him because the story will be in the 1960s. Tiamut will still be gestating. However, maybe that will be the thing that stays his hand if the heroes fail?