Don’t overthink it, look at classic Jansport bags. I’d gone through so many different backpack companies looking for a decent, reasonably priced backpack that wasn’t bogged down with useless shit but still had some organization for my daily carry stuff. I commute to work on the train and have to bring tools, not to mention some odds and ends for sporadic use, rain gear. So I got a bigger one, but it sounds like you could go with the medium size and you’d be right as rain.
It seems like bags these days are really pieces of shit, or they’re these super involved and stupidly expensive bags that are just entirely unnecessary. I’m glad I got a Jansport again. I just wish I had thought of it before I tried like four others that sucked.