I'm not sure the promoted tab adds value to the site. It's slow to update and (IMO) does a poor job of selecting the best posts. Now this wouldn't be a problem since we have top, but it being the default is rather bothersome.
I agree about it being slow to update and doing a poor job of selecting the best posts. However, I do think the idea of having a "promoted" section is good in theory (it'd be nice to have someone curate the best content for us).
I think it'd be a good idea to keep a list of the ways we'd like to see LessWrong improve, sorted by popularity. Ie. email alerts for new responses.
So if you have an idea for how LessWrong could be better, post it in the comments. As people up/downvote, we'll get a sense for what the consensus opinions are.
I think there's a pretty good amount to be gained by improving LessWrong.
Note: I say "ways to improve" instead of "features" because "ways to improve" is more general.