I can't give you amounts but this is what's in mine:
Breadcrumbs
Egg
Minced Onion
Minced Green Pepper
Worcestershire
Soy sauce
Ketchup
Brown Sugar
Onion Powder
Garlic Powder
Paprika
At the end of baking I glaze it with a mix of ketchup, brown sugar, dijon and soy sauce and broil it until bubbly.
It's a bit eclectic but meatloaf haters have been known to go back for seconds.