Great review, Gareth. I found #8 especially interesting.

I wonder about this:

DGW cite various studies showing that people expect to be made markedly unhappier by losses than they actually are if the losses occur, and that people expect to regret bad outcomes more than they actually do (we overestimate how much we will blame ourselves, because we underestimate how good we are at blaming anything and anyone else for our misfortunes).

The so-called impact bias is certainly a thing (I hope to write on it soon for many reasons; I don't think it's been treated on LW), but I wonder if that's not too precise of a bet to be making on the mechanism by which that occurs, at this point, although I'll note that I haven't read the source paper.

Also, I see that there have been some pretty substantial criticisms made (against the original source) by the commentariat (I found this cool/impressive); maybe it would be interesting to include an addendum with the good ones included?

And I assume this is a typo:

That is: why choosing what to spend on, take some time to consider less obvious aspects that you'd otherwise be tempted to neglect.

I imagine you meant to write 'when'.