Firstly, not everything needs a sauce. Bad habit!
Ok. That's a better range of veg then I thought you'd say.
Firstly, how large are your meal plates? To they have an inch wide "lip" around the outside or are they pretty wide with almost no lip? You may need to be aware of how much food your plates actually hold. Serve smaller portions (keep food back in the kitchen, no one will go hungry!) and ensure you both eat slowly whilst also drinking water. This allows you body to register "full" when it is full. If he's in the habit of wolfing because it's delicious then he's probably inadvertently overeating!
Ratatouille is a brilliant vessel for getting veg (and moisture) in! Ratatouille on a crisp baked potato is delicious. I would avoid butter but some grated cheese for protein and that's a fabulously good meal
Make an absolute tonne of it, freeze it in portions and use whenever. Put it alongside any baked, grilled meat or fish.
Homemade spag bol and lasagne using wholemeal pasta served with a side salad. Yes I know he doesn't "like" salads but it's not having just a salad, it's a meal accompaniment. Pack the meat component full of veggies like mushrooms, onion, leek, peppers, anything.
If you're feeling really clever then sub in some quorn mince (50/50) or replace beef or lamb with quorn. It's much much healthier.
DH and I have a version of "en papillote" (in parchment) because parchment is a pain in the arse... So we call it "en foilette" and make it in tinfoil!!!
Raw meat/fish on foil.
Slice lemon/tomatoes/herbs whatever goes with the protein on and under.
Small drizzle of extra virgin and season
Fold up foil to make a sealed package
Bake in oven.
It's brilliant. Meat stays amazingly moist (no need for sauce) and the cooked juices in the packet are flavourful and great on the plate.
Works amazingly with steamed veg.
To decrease carbs, perhaps use baby or Charlotte potatoes? They cover the same space on the plate but are much smaller.