Hi Nick. Whilst I agree with some of your points, I do have some questions.

In point 4 you say 'conventional wisdom says that...'. Given that conventional wisdom can often be wrong, do you know of actual user studies to support your case? Some sites have the most expensive option in the first column and it would be interesting to know of any user or A/B testing in this respect.

You advise having more than one price point to fill in the gap but that's going to depend (at least) on the nature of the product and the actual gap between options isn't it?

You say not to add cents to prices - I have seen it recommended to add cents to rational purchases but not to emotional ones. You may also be better off with $19.99 than with $20. Are your assertions based on any research that you can quote?

You suggest not to 'trick' customers - how is not adding cents different from highlighting a column when the rationale is that without cents a price looks cheaper? Even so I don't understand why highlighting a column as 'most popular' is a trick? It could be useful to some. And while I'd agree that hiding the free plan is something of a dark pattern, if you want to avoid the highlighted column you'll also have to go and change just about every professional ad in existence as they are designed make use of what's known of human psychology to influence people to buy.

Thanks for the article - it's a good topic for discussion.