Have you looked at
MCM Milla bag? For your workhorse, it may fit the criteria. It doesn't have the laptop compartment though and you may have to use the sleeve instead. Maybe you could check it out? I think there's even a thread dedicated to it here somewhere. Or check out the MCM thread.
And my approach;
1. I have to like the look of it.
2. It has to feel nice when I touch it. That's why I usually skip PU or any synthetic material when I shop online, but I'm quite open when I shop in person.
3. No disgusting smell. I don't care if it'll go away later. If the floor one is stinky, it's a sign.
4. The compartments have to make sense. It must be usable.
5. It has to fit me right or let's say I have to look good wearing it. Can't be too small or too big. It has to compliment my figure and my coloring. It has to look good on me.
6. The price should be within my budget and doesn't make me uncomfortable.
That's all.