I'm not sure what it is, but sometimes feels like it's missing from the menu. I can't put my finger on it.
I agree with Kudeebee, just to be sure you have enough, I'd get a little more buns.
Veggies? I'd add a leafy salad or cut veggie/fruit tray.
This was my thought too.
As far as the manwich -- don't add all 10 cans at once. You might not need all 10 cans. I usually use 3 lbs beef for 1 can.
I also agree with more buns.
Good luck and have fun!