Orchestrating characters, for instance. Especially setting up foils. It can be fun, looking back, and realizing, you know, the characters seem to have a certain degree of homogeneity to them. . . .
Deliberating considering what is opposite to the main character and how to construct characters to show that trait up, deliberately choosing character types and assigning them out so that they don't all default to the same type -- well, they are useful writing techniques, but they are not exactly operating by the seat of your pants.
Sometimes when you're plowing through the valley, it can be wise to step back and look at the map thus far.