[Laredo Tugger]

I assume you have the trailer loaded already and those "cubbyholes" came up as extra space.
The one above the fridge looks good for lightweight kitchen support stuff. Boxes of trash bags, zip lock baggies, some linens maybe. Things that wont easily jump out while towing and if they do,no damage.
The opening above the couch looks like they forgot to install the cabinet doors. I would find other Avalanche models (and other Keystone models may provide) that have similar cabinets with that "span" and order 2 doors to match. Or go to HD or Lowes and find the doors, maybe consider another color (white or black with designer doors or a fake glass insert would look nice. If all else fails put that netting material over it with some hooks and call it good for whatever you put in it?
Good luck.
RMc