Do you have time to cook a decent sauce/dinner once a week? I used to be in the kitchen on Sundays doing a roast, so would make a curry, spag bol, chilli, lasagna, shepherd's pie, chicken and mushroom pie....type dinner for Monday as well while I was there. But a dinner for Mon that could easily be doubled and frozen - so only a small amount of extra chopping, but Monday's dinner just needed reheating then, and I would freeze the 2nd (or additional) portions to use another night. I tried to do different things each week, so I would have spag bol on Mon of week 1, but freeze the 2nd portion for thawing maybe the Wed of week 2, while Mon of week 2 might be a chicken and mushroom dish that I'd eat the 2nd batch in week 3....
So if you can find a night where you have time to cook those kinds of meals, even once a week, but do enough for 4 or 6 people in that dinner, freezing leftovers, that makes a big difference. They can be fairly basic, but if you have time, can add extra veg to them too - if I have time to do a big batch, I will get out the food processor to dice the onions (stops me crying) and as I already have that out and dirty, I will blitz a couple of carrots, pepper, courgette, etc and add those to the sauce - they are so small they are hidden from any fussy eaters but both add great nutrition and bulk it out at the same time.
I use recycled plastic takeaway tubs for freezing as they work very well and stack well too. I write the contents on the lids using a sharpie marker.
I have lots of decent jars of sauce in my cupboards to just toss into a diced and fried chicken breast or some frozen (uncooked) prawns and serve with rice/pasta. By "decent", I mean not the budget versions filled with preservatives and sugar, I tend to go for more smaller producers that have good ingredients. And I try to add some veg into those - often it might only be tinned corn or frozen peas, but if I have a couple of minutes, I can slice and fry some mushrooms to add before the sauce, or some peppers to add with the sauce etc.
I also have plenty of things like chicken goujons (I get the ones that are fresh and you can see are made from real chicken, not frozen chicken bits smushed together), oven chips, veg, pizza, etc in the freezer. Lots can go straight into the oven for easy cooking.
I tend to get good pizza, but often relatively plain ones to add our own toppings to (and now you can get relatively long life plain bases, add tomato sauce from a jar, grated mozzarella from a bag, and your own toppings on top). HM potato or sweet potato wedges are relatively straightforward to make and just need 5 minutes to organise at the start (chop spuds without peeling, toss in oil, I microwave for 5 minutes to reduce cooking time by 20 mins, toss on seasoning and into the hot oven, turn once halfway through) and time in the oven.
If you make mash, make enough for 2 nights and reheat it (in the oven, in a pan, microwave) the 2nd night, or use as the basis for fish cakes or similar, or a topping for a shepherd's pie type dish.
If you are peeling carrots for 1 dinner, peel a few extra to have carrot sticks to nibble on for snacks, or to cook the next night.
Some nights, fried egg and beans on toast are fine for dinner. Or hearty soups (HM or shop bought).
There's a deli local to us that does a great deal on a rotisserie chicken, large crusty loaf, bowl of salad and tub of coleslaw - which is usually busiest at dinnertimes midweek. We have been known to buy that as dinner, and use leftovers for lunch the next day (or leftover chicken going into dinner the next day).
I also like meals from the oven. So chicken joints (part boned breasts, thighs, legs), plain or with some feta under the skin, or lemon and garlic over them. Baby potatoes with olive oil (and maybe dried rosemary and dried garlic granules if I'm feeling faffy). Large chunks of peppers and red onions, whole cherry tomatoes (or diced larger ones), maybe chunks of courgette if DD is not eating it (it's not worth the moaning if she is! even though its easy to pick them out)...tossed with some olive oil and seasoning. They could all be in separate trays or all in the same tray, whichever you prefer - but they cook in about 40 minutes, and once you've taken the 10 minutes or so to prep it, can be ignored for the cooking time (maybe toss spuds once halfway through - but not essential). And leftover veg is nice in a plain tomato sauce with pasta, can add chicken or prawns or bacon if you want meat (either cook raw meat before adding veg and sauce to heat through, or just throw already cooked meat in at the same time as sauce and veg).
And for above, cooked meat could be leftovers, or could be bought ready cooked.
Fresh pasta cooks in half the time of dried.