Hi, I have various metal pans, my small ones are 8” diameter, one is 2” deep and the other is 4” inch deep. I use the deeper one for my chicken stock, covering the carcass and skin with about 1.5 - 2 pints water. I usually buy a small chicken that is for 4 people, so that amount of water covers everything.
I stir 1-2 tbsp stock into homemade egg fried rice, couscous, even the dog food. In winter I’ll make soups and gravies. My fridge is great so the stock keeps for 4-5 days; I think it can be frozen, too.
No, my pan is not full to the rim, as I don’t like any spills when I bring to rolling boil, but having a 2/3 full pan doesn’t affect how well the food cooks.
Also, for something like steamed veg or keeping a hot dinner warm for less than an hour, I have got away with using my long handled metal pan.
I think it really is a case of experimenting and seeing what works for you xx