I've put in a bit of effort into running a local self-improvement community (link in Finnish), but one of the problems I've had in making self-improvement be actually a group effort is that a lot of it is actually something that you just need to do yourself.
To be more specific: we can do workshops on dealing with various problems and figuring out your values, we can do coaching meetings where people say what they've done since last time and what they'd like to try/discuss next, we can do coworking spaces... but if your problem is, say, "I need to complete my thesis", there's only as much that we can do to help. At best we can offer a co-working opportunity where there's slightly more social pressure for you to work on your thesis while everyone around you is also working on their own stuff. But you're still the one who needs to do 98% of the work and there's not that much we others can do.
I've personally even had several periods when I've been thinking, "man, I'm really preoccupied with this thing I need to solve... so I think I'll miss out on some of our community stuff because I'm too busy solving my problem". I've heard similar tales from some others - them dropping out of our stuff because they need to actually solve their problems.
I'm not sure how to solve this: if anyone has any ideas, I'm open. The best thing I've come up with is to also have some light social get-togethers, so that people who are busy and stressed with stuff can at least come to events to just relax a bit with friends, without needing to put in the mental energy for some active self-improvement workshop. That, and pairing people up so that they have regular one-on-one peer coaching sessions with each other, which seems to empirically be very useful but also doesn't involve them in the broader community.
if your problem is, say, "I need to complete my thesis", there's only as much that we can do to help
Recommend someone who writes that stuff for money? That already improves one's economical thinking. :P
LW has a problem. Openly or covertly, many posts here promote the idea that a rational person ought to be able to self-improve on their own. Some of it comes from Eliezer's refusal to attend college (and Luke dropping out of his bachelors, etc). Some of it comes from our concept of rationality, that all agents can be approximated as perfect utility maximizers with a bunch of nonessential bugs. Some of it is due to our psychological makeup and introversion. Some of it comes from trying to tackle hard problems that aren't well understood anywhere else. And some of it is just the plain old meme of heroism and forging your own way.