I tend to not be convinced by self-improvement recommendations that aren't explicitly tailored to specific people and their personalities. There are so many variables in play!

Here's how I would theorize about the problem of self-change. Change is hard, it would seem, because our habits are a large complex system that often reinforce our current ways of operating. Perhaps an "extreme" change in one dimension is a sufficient and even the most effective way to trigger systemic change. But in other cases, one might need "medium-level" change in two or more dimensions. It depends on how "the system" (i.e. the person and their environment) are interconnected.

In any case, I'd be interested to hear what people think. For people that try this, please report back.