Privacy Badger is not an adblocker. It block sites that track you by some magic heuristic. It just happen to be that ads are really intrusive. Every time I see a "please whitelist or page in your ad blocker", I get a smug smile on my face, because I do not have one

It's a great combo, although as a developer it's also a constant source of "why the fuck does this website I'm working on not work" because privacybadger is the most aggressive cookie destroyer on the planet.

They work well enough together that I set up any new PC for friends and family with them, after giving them a non-admin account.

what does privacy badger do that can't be accomplished with a custom ublock list?

Mostly automation -- you don't have to actually craft the list. It will just spot stuff it thinks it should be blocking and do so. And if you need to correct it (uncommon in my experience) the UI for doing so is right there next to the address bar. Also, it's capable of just blocking cookies for some sites, which is nice when they're hosting common J's libs/fonts or something, and blocking them outright would break the page.

I ran Privacy Badger for a while. It is very good for finding out who is setting 3rd party cookies or using alternatives to cookies (eg. localstorage with unique identifiers). Rather than using a list, my understanding is it uses heuristics based on what cookies are set, whether they are 1st vs 3rd party, their expiry time and the like.

The good thing about privacy badger is that you don't have to care about the contents of ads ('acceptable ads') or how much you like a particular site ('please unblock us in your ad-blocker).

If a site has parts with 3rd party tracking cookies then I just don't see it.

The downside of only using privacy badger is that you do see some ads. At the moment I find that level of ads acceptable.