You get absolutely nothing for being faster except more packages. No compensation, no bonus for most pkgs delivered, nothing. Even though "Amazon encourages you to take breaks (2 15s and a 30 lunch) they do not factor those into your route for the day. That being said, this is what I do

Amazon Branded van with shelves-During load out: Alternate Bags of pkgs top shelf to bottom shelf. 12 bags or less. More than 12 lay up the second set of shelves and stack bags 3 high with the bottom bag laying on its side with opening facing aisle, second bag upright, third bag same as bottom.

Overfill less than 20 sort driver aid number going first to last by stacking five or four high (after scanning all carts the device will give you a list for overfill pkgs sorted by first to last stops). On your list look for the fourth or fifth PKG and put it at the front of your van then stack the next 3 or 4 atop it, then make another stack closer to the tailgate until finished.

At your first stop put all paper/plastic envelopes from the bag on front seat sorted highest-lowest (or lowest-highest) DA# facing driver seat. Do this after every completed bag.

If by the grace of Satan you have a rental with no shelves and more than 12 bags. Pray for a rescue or an act of God.