Mine has never been able to eat right after waking, even as a baby he would need at least 30 mins after waking in the morning before taking milk. I set his morning timer lights to go off in plenty of time before we need to be out - he has enough time to read a chapter of a book, play in his play room, then have milk and breakfast and then play more or watch TV before getting washed/dressed and another 5-10 mins play before we leave the house for school. He's awake almost 2 hours before our leave time. Not saying to wake your DS up 2 hours earlier, but maybe 30 min earlier hand he can play then have breakfast??
Eggs are great breakfast, I was watching a programme last night about the benefits (or not) of certain foods and the protein in eggs really does help to keep the energy up until lunch time. The other really good breakfast was jumbo porridge oats (rather than quick oats which are processed/ground), the larger oat takes longer to release energy. So porridge, or muesli (I soak DS's the night before so it's lovely and soft by morning plus I don't have to do anything to it, just tip it into a bowl) or some oaty chews or flap jacks (perhaps with less or no sugar/syrup) or oaty biscuits would be great for breakfast.