It may not be a matter of where, but of what. WD-40 isn't a great lubricant in some cases. It's very light and may not work on the nylon parts. It may also dissolve any actual grease that was present.
Maybe try something with Teflon, lithium, or silicone, or use basic 3-in-1 household oil.
It's pretty much all dependent on wattage
For the five kitchen appliances (and one lighting system) described in your post, the answer boils down entirely to wattage/amperage draw, as there are no specific requirements in the NEC for any of them to be on dedicated circuits; the fridge could be on a small appliance (kitchen countertop receptacle) branch ...