No, I haven't. Probably the sort of thing Twitter should have in their own stable though.

They should have better app options for content creators IMO. Not every user in a news-dominated social network is going to be a passive reader.

I don't think a product Tweetbot can exist in Twitter's stable because it cuts all the cruft out of the modern Twitter experience, and is likely the opposite of the direction Twitter would like to go.

It has kind of happened already — Twitter bought Tweetie, which was a well-liked desktop client, and then let it languish.