dpeending obviouly on how many children you end up with, and what facilities, and what age range, etc etc, what they do at dd1's school might work for meal times.
you would need to stagger, just for logistics.
but dd1 mkaes her lunch each day, sets her place and tidies upafter.
so, I send in her food - whether a sandwich (I just send the bread plain, she makes the sandwich) or a "hot" meal - either to be cooked (if frozen, bung in microwave) or partly cooked to be heated (eg spag bol, all done, needs heating up).
this take scare of the diet aspect - I know what she is beign fed. and she gets to practice cooking/odd bit of stirrign/chopping etc. she lays her place out (placemat, cutlery) and that of her tutor. and other pupil if they are eating at the same time. she clears her plate (scraps in bin), and puts in in the sink for washingup. a couple of times a week it is her turn to do the washing up as part of her daily living skills. wipes table, etc.
I think you could get htis working for eg 5/6 children at a time, within a routine, so you would need ot stagger "cooking" time into 3/4 groups (depending on numbe rof chidlren), but as this is minimal as it is more about heating up, then it shouldn't be too hard.
I don't find it that hard to send food for dd1 - leftovers form what we have the night before, batch cook and freeze etc - you adapt to what oyu know. I would find it harder to put together a lunchbox day after day, I htink, and certainly more stressful to not be in control of what she is eating (even something as little as eating a different type of raisins can have an impact on dd1, both bowel wise and behaviour wise), so I don't think that asig parents ot send in food would be that much of an issue necessarily.
Good luck with this - I am fairly heavily involved in policies and steering the curriculum at dd1's school, so if you need anythign, please ask.