Found a link: https://www.walmart.com/ip/Outdoor-Products-Quest-Backpack-D...
I purchased my first TimBuk2 backpack last year and was ecstatic about it: https://www.timbuk2.com/
Basically, I realized that pretty much the only thing I needed to carry to and from work was my laptop (13" MBP at the time). I had a few other things like earphones, ibuprofen, etc. but they all fit inside small compartments in that slim backpack.
That was my favorite commute backpack by far. On the train, it lets you not take off your backpack, and still not be a bother to others. It satisfies your bonus points for water/snow resistance if it's raining or snowing, because you can just wear it underneath your bigger jacket.
Got an Ogio backpack from Rackspace back in 2012 and I've been using it at 3 different companies. Each time I'm asked about why I use a Rackspace backpack at Company X I challenge them to give me a better backpack for free. No one has matched it yet.
This little guy has so much room in it that I can pack laptop+accesories+clothes for 3-4 days. It is also waterproof (I used to cycle to/from work in British weather for 2 years) and durable as f*ck.
I like it so much that I bought a second Ogio backpack so both me and my wife can pack stuff when traveling with the certainty that we won't have to buy a new backpack every year or two.
i bought a north face borealis in 2014 and it looks as good as new, not a stitch out of place.
osprey i hear is good as well.
It has held up great for daily commutes as well as 2 day official trips, enough space to carry all.
https://www.amazon.com/Thule-Crossover-32L-Backpack/dp/B004X...
Don't carry a laptop unless you are working during the commute or have some other restriction. It is better to be able to access all of your systems remotely, so you can pull anything you need from them.