Ends tend to be the easiest. The big confrontation is obviously the climax -- even though then I have to work back the entire way to the inciting incident. And then figure out a way to obfuscate it. Just because it's obvious to me doesn't mean it's tolerable if it's obvious to the characters, or the audience.
Inciting incidents are also fairly easy to recognize. They set things in act by setting things out of whack, creating a discord that has to be resolved. Mind you, if they don't suggest some immediate courses of action, they can still be a bear to develop. Even they give the obvious first step of having the character be confused about what to do next.
Unfortunately, my muse tends to like ones in the middle. That can go all over the place. Even if it's a big shift, there's a lot of places for plot points. And plot points really can move about the tale. Sometimes I put it as early as possible, on the principle that if it doesn't need to have something happen before it, I might as well. Except that then I need to develop its consequences instead of its antecedents.