I enjoy updates about what didn't work the most. They usually teach me more than the success posts.

Same here, the "this didn't work and here's why" posts get the best replies. My favourite format is one decision I was stuck on, the options I had, what I picked, and a screenshot. It gives people something concrete to push back on.

Showing the options and the decision gives people something concrete to respond to. I’d find that more useful than a polished win on its own.

Same. A polished win tells me what happened, but a decision with its options tells me how someone thinks, and that's what makes me want to follow along.

The options-and-decision format is a good way to invite useful feedback; I’d add what evidence would change your mind, so readers can respond to the actual trade-off rather than just the outcome.