gt maybe you need to alter your routine if it isn't working. It will take a while to find what works for you. It sounds like the kids only need a light supper when you get in, so either, something that takes almost no prep, like cereal, or pre-prepare a weeks worth at the weekend. Tupperware with chopped up bits of cheese and a separate Tupperware with some chopped up fruit like mango that they can have with crackers, or a load of chopped up veg with a mini yoghurt perhaps? Bagel and cream cheese.
You need quick and easy teas. So you have a slow cooker? You could do a job lot if something and freeze portions that you can grab out of the freezer In The morning to defrost while you are at work. I used to set the timer on the oven sometimes with jacket potatoes in and then throw a quiche in the oven with some salad. My other quick and easy was always just some pasta with pesto stirred through and a load of chopped up cherry tomatoes, maybe with some cooked chicken if I had any leftovers. Or another super qUick one is a chickpea curry just using chickpeas, chopped onion and garlic, a bit of curry powder and some stock I think. Then I stick some cherry toms in at the end. I always put that together while the boys are having their tea and stick it on a really low heat to bubble away. (I also keep in a load of those spice mixes from Quality Foods 
for quick ones)
Anyway those are like Of my ideas.
The other thing I used to do when I was working was lay the weeks clothes out in the boys rooms on a Sunday night, that saved me time every evening.
Xx