Of the ones I've used I like Reddit the most. It allows long posts, uses Markdown, and is threaded.
> We've explored so little of the design space.
I've recently started writing a federated blogging platform which will use the ActivityPub protocol. One nice advantage of federated platforms, is they can share each others' messages meaning it's easier for them to get lots of users (you can piggyback on the rest of the federation), so there can be more experiments on doing things different ways.
> You have to wait at least 30 seconds before you can hit the reply or reshare button.
Or the message isn't sent until a cooling down period.
> Short or low-information comments are discouraged; if your comment is short or an exact duplicate of something previously written (e.g. a common insult), it's blocked or you have to wait longer before posting it.
Sometimes a post can be short because a short post is all that is needed. E.g someone might ask me a question that the answer might simply be "yes". I would find it annoying to have to artificially pad the length.
But longer posts should always be possible and the user interface shouldn't discourage them.
> You must listen to your comment read back to you aloud before you can post it.
That's an interesting one. The way I'm going is posts will be edited in Markdown and will then appear as marked-up text.
> Even when reshared, your comment is always presented together with, and close to, the content of the original source article so it's hard to ignore the source.
What I call the "context" of a post is the post its a reply to and that post's context. This could all be stored in a data-structure (such as JSON) when the post is transferred across the network, so the context would always be there. Also the id of a post could be a hash of its contents, making it tamper-evident.
