I'm a heavy (2-4 flights/week) traveller, and love my North Face 'Router Transit' backpack: https://www.thenorthface.com/shop/equipment-backpacks-mens-b...

I usually lug around 2 laptops, a huge USB battery pack, misc. USB accoutrements, snacks, Bose over-the-ear headphones, and occasionally a (slim model) game system in it without it being too overpacked or bulky.