I need better ways to connect related ideas, (and to see how others have connected them)! Tags are one, non-exclusive way to relate ideas—I'd suggest, for example, a field that let me group specific ideas explicitly, including ways to easily look up another idea without losing my place….

Bookmarks offer another, limited way to help organize ideas—I'd suggest, for example, a way to create multiple collections, then share and/or collaborate on those collections.

I think this would help characterize closely related, but not entirely duplicative ideas. And also help make the organize related ideas expressed as both "business requirement" and "implementation", to help highlight the most flexible and impactful design possibilities.