I've been using a Lido 2 hand grinder for coffee every morning for almost 12 years now. More recently (~7 years) I've settled on using a Chemex to actually make my coffee. I'll likely keep using this setup for the rest of my life.

I also have a cast iron and I struggle with seasoning because all the burners I've ever used are just a bit too small for it (common electric ones). Soon I'll buy a torch (like for making Crème Brûlée) and maybe some sunflower oil to experiment on getting a reaallly nice coating on it. Sunflower oil has I higher burn temperature, so I'm thinking it will improve the longevity of the coating, but we'll see.