: It could have ten missions, but each one just takes longer to complete. Or it
: could have twenty shorter missions.

: I for one am expecting about what we've seen in past Halo games. Sure, the
: number of missions vary, but I don't feel like any one of them was
: drastically short or longer than any other. Not significantly enough for
: me to have noticed it at any rate.

To add to that, look at some of the par times in the MCC:

Uplift Reserve 3 minutes
The Library 25 minutes

Clearly the level design is going to have more of an impact that the number of missions.