State handeling in Flutter with multiple pages

I'm trying to figure out a good way of architecturing a Flutter app. I have several pages, which can navigate to other pages. Data modified by one page, might be used by other pages and needs to be updated. I recently started using the Provider package. I let each page have a model which implements ChangeNotifier and set a ChangeNotifierProvider above the MaterialApp. Now to update the data for other pages, i have to get the other page's model and call an update method on it. It's quite messy. I use Firestore, so i could listen to database changes, but i want to avoid too much magic. Also, sometimes it makes sense to just send data from one page to another, without using a network call, or pass data back in the Navigator.pop method. I find it hard to make good choices in how to solve this. I should probably look at a more refined architecture like redux or mobx. Or just go for a vanilla solution and use lot's of callbacks for all the various events. Those big'ol models per page, seems a bit bit bloated and messy after a while. Do anyone have a similar experience in Flutter how to architect these things? Confused