I've given up trying to wrangle my inbox and instead just let Google do it's thing with the different category tabs. I never open "Promotions" or "Social" and only rarely need to open "Updates" (mostly to drag something into the Primary tab).

Am I missing things? Yes, it has happened, but I feel like I'm missing less than when my inbox was a superfund site. Email has so much more noise than signal for me at this point.