The first few scenes actually worry me quite a bit. It's hard to describe but it seems light to me.
Many have said that the comics have humor in them and they are right. I don't think humor is what we're talking about here. I think it's more the general tone of the movie.
This comes from the acting and overall directing of the movie.
You can have a very serious and even heavy movie with humorous moments.
You can also have a movie with no jokes which just seems light, or doesn't take itself seriously.
it's the difference between real movies and some teen disney movies.
What I call power ranger acting.
The new Star wars have that quality to them.
Based on the acting we see so far, reed's reaction, Thing wiping tears, Johnny's comments, and just the feel of it, for example the slight smile reed has on his face as Johnny runs past him, to the comedian priest guy, all this thing give me a light beer impression rather than a real movie impression.
IMO, armagedon and the invincibles capture the Tone of the FF comics perfectly. Humorous but real, serious and heavy, at the same time.