So I ordered this, having seen the Amazon Basics knock-off version of it:
Proper Roady Photo Full Backpack, by Crumpler
It's been utterly fantastic for carting camera gear and a latop on planes (or any other time I need to travel with the "full kit". It holds a ton of camera gear and a 15" laptop, fits under-seat if it needs to, and is fairly comfortable once all the straps are adjusted right.
Here it is:
