But you don't know what tone is really until you see how it's presented. That's my point with Dr. Who. ( I agree Who is the right tone for FF though)
If I just told you he's coming back after committing genocide to his entire race and has been traveling alone brooding. That sounds dark, but the series isn't presented as dark.
A fantastic four movie with them wearing outfits to help with adapting to their powers isn't dark to me(or embarrassed about the source). It's just different. Until I see how they present the "disabilities" on screen. It's just words. If Reed's skin is constantly falling off or Torch is setting nurses on fire then it's dark.
If Torch is just put inside a "cold room" to keep his body temperature down until he gets his containment suit isn't dark, imo.
It's dragging out their origins which could be annoying.

t: