I find that freezing small amounts of leftovers with good intentions just fills the freezer with oddities that don't get used so I try to avoid having them.
I'll normally freeze most of the freezable things I buy straight away, like meat, then only defrost when I'm certain to use it. This makes a big difference and means it's not difficult to change the meal plan at short notice. The main driver for the rolling meal plan (I plan about 6 days ahead on a rolling basis) is whether a meal is accompanied by salad or veg, and what fresh salad and veg I'm trying to use. This week I swapped round Monday's casserole and Tuesday's lamb kebabs because the salad that came in the delivery yesterday was shorter in date than I hoped and needs to be used quicker. Because the lamb for kebabs and the batch cooked casserole are in the freezer until the night before I'll use them, it's not a problem to switch round.
Freezing meat as the default and defrost as you need it also means I'm freezing it at its freshest, rather than as a last resort.
No individual yogurts here either (more on the grounds of sugar than waste though), big tub of plan yogurt and ypu take a helping amd add a swirl of jam, or some fruit, honey, nuts etc as you fancy. Yogurt tub lasts forever but I can hasten its conclusion by cooking with it too.