I'm certain you know a lot more than me on this and the best ways in which TIW is growing - I would suggest, however, such an idea:
By focusing TIW community on creative writing as a whole, (excluding poetry) and in that still implementing different windows for different specific types of writing to narrow down the content further, (short stories for example) whilst fully migrating poetry to a brand new community and also splitting that up into different windows for different types of poetic writing or themes, (this could be worked on and discussed) - by doing this, both writers and poets could reap many benefits of having permanent communities available to them to share with and engage with.
Of course, the manifestation of such an idea is easier said and thought of than actually done... I would strongly suggest thinking about a strategic and well-timed post to TIW community, throwing the idea out there, calling out to anyone interested in undertaking such a project. Seeing the poetic crowd usually on here, I am certain some would step up to the task.