It would be really helpful if you could have both Design pages and FigJam pages in the same file. This would make sure that everything related to a project exists in one file, which makes it easier to get the whole picture and collaborate. It also makes it easier for others to take over or update a project.
The way I see it is that when you open a new page you are asked if it is a Design or FigJam page in the same way you are asked for a new file at the moment.
(I know that similar ideas have been opened, but they have disappeared from the features list. https://forum.figma.com/t/feature-idea-figjam-inside-of-figma-project-files/4427 404s)
