I know you said not too much pasta...
these 2 are not bung in the oven ones, but they are fast and simple.
Boil water, add pasta, a few minutes before the end, add frozen peas and frozen green beans. Boil until all cooked. Strain, pour in serving bowl, dump pesto from a jar on top, stir and stick some cheese on top. Takes 15 minutes max, including waiting for water to boil.
Boil water, add pasta, when cooked, strain and put back in pan. Add passatta from a jar and mini mozzarella balls from a bag and heat for a moment or two until warm, but moz balls not completely melted. Tip in serving bowl with a few fresh basil leaves on top. Again 15 minutes max.
Fish fingers, beans and chips! Bung in the oven / microwave
Jacket potato with beans and cheese, tuna mayo and sweencorn, or whatever you fancy. I always find as long as you put a bit of salad on the plate, it looks more like a main meal. I microwave potatoes, and oven at the end to make them a bit crispy. You can buy the toppings as sandwich fillers if you do not think you are well enough to prepare.
You said not much meat in the house, but ham egg and chips makes a good meal, and you could use fake ham instead. Its a bung in the oven one, bar the fried egg.
Sausage and yorkshire puds (bung both in the oven) for a deconstructed toad in the hole, served with whatever veg you have in the freezer which can be nuked in the microwave. Gravy can also be brought!
Thats off the top of my head...