I think it is important to answer why people go to LessWrong and whether it is perceived to be primarily a place where you go to improve one's rationality that happens to be an internet forum, or an internet forum where you can read interesting things, such as rationality (I think that experiencing an intellectual journey is somewhere in between, but probably closer to the latter). Because there are a lot of large forums where you can read a lot of interesting things - for example, r/askscience and r/askhistorians have hundreds of thousands subscribers and a lot of contributors who produce huge quantities of interesting content.

A place where people go to improve their rationality can take many forms. It doesn't even have to be a blog, a forum, or a wiki. If I allowed myself to be a bit starry-eyed, I would say, that it would be really interesting, if, for example, LessWrong had its own integrated Good Judgement Project. Or if LW had its own karma (or cryptocurrency) denominated prediction markets. Of course, ideas like these would require a lot of effort to implement.