I like Panko.
Meatloaf is whatever you want it to be, except maybe tofu...
But there are themes, bacon, bbq, chili spices, ketchup. I got some truffle powder, and I've added a little of that at times.
We have a double meatloaf pan, the inner pan has holes and the fat drains into the outer pan. So. if you get adventurous and add a rich sausage, you won't pay too high a price later.
Has anybody mentioned worcester sauce? I use that stuff a lot.
https://www.epicurious.com/recipes/food/views/rustic-french-meatloaf-352292
If you use chicken livers, because pate is really just French for meatloaf, I strongly suggest getting organic or Bell & Evans at Whole Foods.