You can also keep eating eggs but reduce the amount of yolks you use. Plain egg whites are super depressing, but mixed with salsa and wrapped in a tortilla, or made into a quick fritatta with spinach and feta, they can be made tasty. My standard omelet is one whole egg plus two whites. (I do always feel guilty throwing away the yolks. But, I decided there's nothing to be done about that.)

I'm with you, I get hungry by 10 if I had no protein for breakfast. I usually get it from fat-free yogurt, mixed with muesli (which has dried fruit, but no added sugar). Cottage cheese would also give you some protein, and can be mixed with savory things.