Can you perhaps show off your characters and what's happened to them in different mediums (if your setting allows for it)? At the end of my WIP, my MC is sat drinking in a bar (this in itself is something that tells a story about her state of mind four months after the climax of the novel). She then sees her old partner giving a press conference on a TV screen in the bar, which is a springboard for the MC to talk a bit about what's happened to that character since then. It feels more organic and less contrived than having them bump into each other in person. Another tactic might be to end your climax in such a way that what happens to some characters in the following months is obvious (or of no consequence) so you have fewer stories to wrap up in the denouement.

As for length, that's tricky, but perhaps it doesn't need to be longer? As long as your reader feels it works, that's the main thing. Have you run it past any beta readers?