I'm not sure if it's a growth issue, or if I'm just getting tired of it personally, but the spamming of identical URLs over multiple instances is getting out of hand. Even worse when I block one post for whatever reason, only to have to repeat the task upteen number of times because one or more users (usually one) "helpfully" post the link in every tangentially related community.

Instead of that, it'd be better to have the front page (all/local/subscribed) automatically group any post of an identical URL into a single "post". In essence, each new post of that URL would create a separate discussion thread to the given community, and each thread could be listed under the "main" post similar to how crossposts currently are instead of cluttering up the front page.