I never monkeyed around with breakfasts, though I do know what you mean about them not feeling like enough many days. I have hot tea or coffee to get me through to lunch -- that and keeping very busy. Good luck with your experimentations and finding what works best for you.
I had a NSV, of sorts, yesterday. About 1:30pm, my precious, sweet little dog started having a seizure. I had never seen anything like that before. I ran out of the house with him -- later realizing that I left the front door wide open -- and rushed him to the vet. I thought he was dying. (Hours and many $$$ later, it seems as if he will be fine. No systemic reason for it, from what they can see. It may be epilepsy or it may have been a one-off, time will tell.) Anyway, when we got back home with him, my son tore into the graham crackers. Being a 13 y/o boy, I couldn't tell whether he was hungry or eating out of emotion. With his current metabolism, it doesn't much matter. I had the same urge -- stuff my face with carbs -- and that is the first time since starting IP that I had that sensation. I didn't. Instead, I went and made myself a huge mug of screaming hot (takes longer to drink that way) coffee with every "fake" addition I had in the house -- sweetener, a bit from my evening shake (for a creamer), sugarless syrup, WF chocolate sauce -- I made the thing into a real, but legal, treat . . . and it satisfied me. Not one extra calorie was taken in. This is a huge lifestyle change for me -- in the past, this would have warranted an entire bag of chips.
NO GRIT, NO PEARL.