I've started doing one order at a time.
For the past few months, I've only been doing one order at a time. I got tired of people being being upset and filing false reports on me because they were mad about their food being late. Now I take one order, stop new requests, and log back once that order has been completed.
I'm still making about the same amount of money if not more. I send my customers a text while I'm waiting on their order that lets them know I only do one order at a time because I care about the quality of their food. So many people raise the tip after that and I'm getting a lot more thumbs up in the app as well.
So it is possible. If you let people know they are basically getting priority for free, they will reward you for it. It's nice to see people with a smile on their face when I roll up. It's even nicer when that fat tips comes in because their food was still piping hot.