So, change of plans: originally, I meant to go with Rigify's standard single toe policy and add individual toes later. But for bare feet a single toe bone simply can't bend right. I kinda had an inkling of how to add proper toes with Rigify (basically like one does fingers) although I wasn't feeling very confident yet about tweaking the metarig on my own. Fortunately, there's a cgdive course that covers it (for an actual skeleton figure, but that's close enough) which means I'll have my guard wheels. Then I realized that it's probably best to add a little bit more detail to the foot mesh anyway in order to support individual toes, so it's a good thing I'm thinking about this now. Apart from needing a couple more edge loops per toe, I noticed some ugly artifacts with the single toe bending due to badly placed poles, so I'm fixing that, too.

-- I'm not mad at you, just Westphalian.