If I remember the math right, 3 cans is good (even if Henry doesn't think so yet).
All the foods you are giving are 4% or lower, so it won't be carbs causing wonky numbers if you see them. The only thing I can suggest carb-wise is maybe make his overnight meal a 6% or 7% Friskees maybe? See if the extra carbs offset his "feeling low overnight" that we have thought might be happening and knock out part of the possible "dawn phenomenon" thingy?
He might even get a few more calories off the Friskees, which might pacify his grumpy "But Mommmmmmmm, I'm hungry!!!" feeling...
Carl