Same workflow here, and it's become a breeze with autofix, rebase --update-refs, and a small command to push the whole stack.
I'm using magit, so I directly see what could not be matched and remains staged.
Yes, I empirically found the hunk-based approach of git autofixup to work more reliably. I use it via magit.
Paired with rebase --update-refs, it's particularly helpful to automatically fixup stacked branches.