Oh, also, another idea: maybe a mindmap feature, kinda like a brainstorm place to brainstorm ideas for visual thinkers! Don't know if it's in the scope of what the app is used for, but that would be great to have it there so everything regarding game production stay in one place rather than being scattered in lot of different apps!
Another one linked to it: I'd also suggest the possibility to open and split tabs/windows of different workspace of the app so we can access for exemple the brainstorm/moodboard at the same time as other notes place so we can put down what has been "in the more vague" brainstorming phase on the more concretes docs so we can visualise everything more easily while working from one step to another, from pre-prod to more production ready!