You need as many of the following as possible
Microwave
slow cooker
toaster
steamer
rice cooker
Deep fat fryer
Slow cooker - stews, roasted joints or whole chicken. You can also do a cooked breakfast over night.
Toaster and toaster bags for toasties, potato waffles etc
Steamer - do the veg to go with the roast in the slow cooker. Wrap meat and seasoning in foil and cook in with the veg.
Rice cooker - add dry rice, spices, coconut milk and fish (salmon works well) obviously rice and you can do things like a frittata or omelette type dish.
Microwave - cook 'poached' eggs in ramekins, if it's a combie you can do yorkshire pudding. Sweet potato 'mash' in the microwave is easier than other mash, just stick a sweet potato in on full for 5 mins, then turn over and cook for another 5 mins. Cut it in half and just squeeze out the 'mash'.
Baked beans with grated cheese in to pour over the toast you do in the toaster.
You can use the fryer to fry potatoes steamed in the steamer to make a sort of fake roast potato.