Stores for everything. Modal stores; enforce open modal business logic app wide. Menu stores; allow customizing menus via config or plugins. Event store; app wide event bus now you can know when specific components/widgets rendered for the user. Theme store; wrap light/dark media query for system pref and user override in an observable.
Keep any and all business logic out of components if at all possible; that's my moto.
Keep any and all business logic out of components if at all possible; that's my moto.