I wonder if it'd be a good idea to make this kind of posts for all pending PRs, to solicit feedback? I realize this one might be a bit more geared towards feedback than others, so maybe not every PR should be shared, but it's still probably a good idea!
Yes, I think in general, it's good to ask for feedback here.
As you mentioned, some PRs might be better suited than others.
For example, stackers might have have more feedback when it comes to feature PRs compared to bug PRs.
I think this is something every PR author can decide for themselves :)