@syntax I mean minimal OSes (Arch Linux ARM, for example) can certainly help SD longevity but really I think you're just sort of minimally prolonging the inevitable. Just be sure to make regular backups to an external storage device and you'll be all good.
@ThreeBadgersInATrenchcoat I agree. I've done all I can for now / all I have the patience for (disabled logging, swap etc.). Other than that I'll just keep an eye on performance, clone the SD every month or so.