I used Citristrip. Remember how the doorknob and plate looked a few days ago?
Here it is now. Ta-dah! Shiny.
And here it is with the rest of the hardware in various states of the stripping process.
Unlike the wood, I only need to leave it on the metal for a half hour or so, and the paint wipes right off. I used a turkey lacer to gently rub it out of the grooves. (It's the long metal needle-like thing with the curved end, on the bottom piece of paper towel.) For soaking, I use a disposable metal tray with a lid. (In this case, a pumpkin cake mold.) The lid keeps the Citristrip from drying out, and I can reuse it again. Afterwards, I wash everything in mild dish soap. It's important to bag and tag everything so as to remember where all the parts came from--there are dozens of tiny screws, in different sizes.
We won't be doing anything to polish the old brass parts; I rather like the patina. And even though the polished nickel has worn off in parts, we won't be replating it. I want it to look like the hardware has been here for generations.
I think this is even more satisfying than revealing the old wood