I'm pretty sure that this is a far more vague answer than you were hoping for, but in my experience -- in plots or in fiction writing -- a story takes the time and space a story takes.
What you need to look for is not page count or the number of days it takes to resolve: It's reader/player engagement. As long as your players are happily pushing on and moving forwards, you're doing it right. If they start to slow down, get distracted, grind to a halt -- then you need to push the story onwards, whether by means of a new set of clues, something dramatic opening the next phase, or introducing new people.
It's very much a listen to your audience thing. And in that, not at all an easy thing because some players seem wildly excited and then suddenly lose drive without much warning. Other players start slow but stick with you until the end. A lot of them get distracted by something shiny elsewhere, and some turn up in the middle, asking if it's too late to join.
The ones you want to try the hardest to please are the quietly loyal ones -- who are often not the ones you'd think of first when you think of potential people to include. As it happens, the highly active, widely well known players are typically the ones who get the most offers, and you may easily find that the ones who are most grateful to participate are the ones whose names tend to be on the fringes. The ones with small children, the shy ones, the ones in odd timezones -- people who may be ready to bend over backward to be included in something that's set at a pace they can keep up with.
A large part of your decision about pacing making needs to revolve around that: Your player segment of choice. Some people have every night all week in EST. Some people have two nights a week, some are in Singapore or London, and some are online 24/7 but suffer from so much fatigue that a few poses a day are all they can manage. Which is your tribe?