excellent tui for selecting chunks like incommit -i. Arrow keys quickly fold and unfold files/chunks/individual lines

git add -p might not have a fancy TUI interface but it supports picking files/chunks without an issue. I'm not sure how this could be described as a UI problem.

commits come in 3 categories:

I'm not sure how that would be useful in Git's perspective. In Git, public commits are commits pushed to a shared remote repository, and draft/secret commits are just local commits that you don't push. I'm not sure what value those specialized types of commits add.

Git's approach sounds simpler, consistent, and coherent, and thus simple to learn. I'm not sure what was gained by pushing that level of complexity onto Mercurial.

when you rebase, your previous commits are marked obsolete and hidden from most UI.

I'm also not sure if that makes sense. If you rebased a branch, you don't expect the original branch to stay there. As the name implies, what you want to do is to replay a sequence of commits onto another branch. In the rare cases you wish to keep the original branch in place, you just create a new branch alongside the old branch and rebase the new one instead.

Keeping the old branch in place after rebasing it feels inconsistent and illogical.