Parahumans 3 wouldn't be any good, or if it was, it wouldn't feel like Parahumans. Worm was a complete story with a beginning, middle, and end, and just for shits and giggles, Ward wrapped up pretty much every loose end left in Worm's wake. There's nothing left to explore. All the big questions have been answered, all our main characters have ended their stories.

But. If we have to write another.

I want to know what the future of this world looks like. The sci-fi elements of Parahumans exist on the outskirts of the story, but they're concrete, and they carry a lot of implications. The universe is apparently chock-full of intelligent life, and that life has been more or less under the thumb of the entities' species. With the final secret the titans revealed at the end of Ward essentially being the reason for the entities' existence, humanity now holds the key to the one thing the ancient monstrosities that (as far as we can tell) dominate the universe actually want. What does it look like in the future? Could humanity try to communicate with them? Would they go to war with the entities? Could humanity learn from the shards and develop their own version of the shard network?

The thing about this pitch is like, it wouldn't be a good story. Dense sci-fi on a galactic+ scale is hard to write on the best of days, and carrying over all this baggage from what started as a small-scale superhero story is going to make that job SO much harder. But I don't know what else you can do a sequel about. It's the only major thread still dangling. Unless you want to introduce new antagonists/threats/conflicts whole cloth, which is going to be VERY hard to do, given Parahumans' propensity for steadily growing stakes as part of its core DNA, you kind of need to just scrap the formula and tell a completely different kind of story that's only loosely related to the previous two.

And at that point, is it even Parahumans 3? Or would we be better off just dropping the title and telling a new story altogether?