I bought this bag in aubergine for my wife as she needed something more casual and a little more space for stops around the town and picking up small items from the store. Overall, she loves and uses it quite a lot.
Her comments generally have included what others have said. In her bag's color, the inside is very dark and hard to see darker items. The bag would be better suited with a lighter liner of some sort. It probably would not even need to be as high quality as the Halcyon. Also, some sort of slip pocket for very basic organization. Nothing elaborate, but maybe a section to put heavier items so they don't flop around and trample other items in the bag. A last bonus item would be a small interior zippered pocket to hold smaller items that you would not want exposed on the less useful exterior zippered pockets. I would suggest removing one of the exterior pocket inside and making it slightly larger. Lastly, she likes the capacity a lot and is fine with it. However, the straps could be a couple inches longer as it rides very high slung over the shoulder.
Though those changes would add some cost, I think they would elevate the bag up a notch. I would have paid an extra $25 for it if it had most of the suggestions. Unfortunately, we would probably never get an upgraded one because Tom Bihn bags are built like tanks and hers will likely never need replacing for a very long time.
Overall, a very good bag with even more potential possible.