Of course I like this idea: I've written a book like it myself. Mine's about Montaigne, who, unlike the others, wasn't a novelist. But he might as well have been, because he explored different points of view and contradictory opinions, and avoided laying down rules. Like good novelists, he observed what people actually did rather than telling them to do something else.
Perhaps this is why it's more appealing to get "life tips" from fiction writers rather than from professional psycho-gurus. It's a lot better to observe someone else being silly, misguided or self-deluding, and to learn something from it, than it is to see Moses come stomping down from the mountaintop in your direction with a slab of commandments under his arm.
Vaguely connected with this, I've also come across a blogging project called "100 days to make me a better person": horrible idea! But it includes one blog I really like. The author has just started uploading one photo a day, for a hundred days, in memory of a recently deceased friend. The idea is to take proper notice of life, at least for 100 days. It's called 100 days (Happy to be Alive) - a much more appealing idea than trying to make oneself into a better person. (Or maybe it's just a better way of being a better person..?)