Gosh that is a long time to cook for so many!
Do you have big enough pans?
I think going for few dishes makes it much easier re knowing how much to buy and reducing faff factor.
Sandwiches... most people have sandwiches every day at work!
Trays of roasted chicken thighs - do one tray plain for the children/fussy adults and other trays with herbs. Or even just buy whole roasted chickens.
Crusty bread.
Slaw type crunch fresh salad.
Lamb shoulder slow roasted in the oven OR lamb kebabs in the oven.
Pita breads
Cucumber, onion and tomato salad
Red cabbage salad
Tadziki
Chili sauce
Soup and bread rolls with cheese and ham
Risotto.
Lemon and chicken and olive tagine with couscous.
Mild curry and rice. Mild chilli and rice. I don't care if people 'don't like spice' there is a bit of eating what you are given!
Chicken fajitas (mild)
You can roast the veg in the oven, fry the chicken and have chopped letticue, cheese, salsa and guac and fajitas on the table.
Lasagna with garlic bread and salad. If you buy fresh not frozen garlic bread you can do it in the oven after you take out the lasagna and it will still be hot if you covered it.
Bangers and mash and gravey with peas and cabbage (not v summery)
Sausage and bean casserole with crusty bread and green beans
Chorizo, tomato and butter bean stew with white fish (I'd use the frozen cod fillets like from tesco and do those in the oven whilst you do the stew on the hob)
Prawn, green olive, fennel, yellow pepper and tomato stew with rice
Basically just thinly slice the fennel and peppers and fry them, add in some sherry or white wine, season and a pinch of turmeric then chuck in tinned toms and olives then just a few mins before finishing add the defrosted prawns.
Fish stew