Load order, weight balance and labeling that survives the move.
Packing a tote is not the same as packing a box. Because the walls are rigid, you can load to the rim without worrying about bulging sides.
Load heaviest first
Books, tools and pantry goods go in the medium totes. Keep them to a weight one person can lift comfortably.
Label the short side
Write the room on the short end so the label stays visible once totes are stacked three high.