Users add tags to replies?

If I can pitch in a reason to add it:
we have one topic for lets say all Poems, instead of multiple topics for each Poem. As well as many other, singular topics for multiple replies/posts.
Each reply poem may want a different tag, of course, concerning the content of their poem

Right now only topic starter or lvl3+ can add/edit these in, instead of the user themselves.

Make sense?