I'm planning a six night rafting trip and I take along a bear canister. If I can't fit everything into the canister, I leave some stuff out that's packaged well. Like a sealed bag of chips. After the first day the space isn't as critical.

I always take canned food rafting, and leave it out. Do bears get into cans?

Vacuum sealing grains for dinner is a good idea but not necessary. I like to add the salt/spices to the rice while I'm packing it.

I don't think I could ever plan this with a spreadsheet. I just take along a lot of stuff I think I'll want to eat and eat it. As long as I get a good hot dinner at night I'll be happy.