If the only differentiator between this and the competition is the length of the content you're in for some serious trouble. It looks like a Medium knock off and I don't see the appeal. It's not like Medium keeps you from writing a short post.
Boundaries are important. Boundaries define entire new worlds of content. It functions way differently than Medium. It's a follow/follower feed structure. Medium doesn't prevent you from writing a short post, but we all feel the psychological pressure to not publish something on medium unless we have at least a page of writing. For this reason, blogging is very inaccessible for most people, and most of our daily thou…
I would say your other competition is Tumblr, which can be adapted for short, medium and long content but seems overwhelmingly to be used for slightly-longer-than-twitter posts.