Unless I'm so far out in left field, I need a road map to get back to home base, I think TB needs another offering in the small size messenger bag department. Something bigger than the Imago, smaller than the ID. They have two mid-sized ones, why not two small ones?
The Imago clocks in at 825 cu. in with no outside pockets for water bottle(s), just ones for accessories. The Id is 1275 cu in, although with an outside water bottle pocket. Maybe I'm kvetching, but the volume of the Imago is greatly lowered once you have to pack a water bottle inside of it. Also, in many instances, I would not be keen on opening my bag and exposing the contents to strangers in certain areas, just to get a drink of water.
I'd love to have TB offer a "packable" messenger bag. One you can cram in the main bag, when you travel (I hate traveling with two bags, because you are overpacking); so it must be crushable, light, and just big enough to hold a daytrip's worth of supplies. Yes, I know the Synapse 19L bag would be ideal, but I prefer, and I know I'm not alone in this, a messenger bag in crowded areas for security concerns. I used Pacsafe's 825 cu. in. messenger bag previously, but it is not a TB engineered product and it showed.
The Imago would almost suffice, but not outside pockets for water, so that's out. The Id is too big= would eat up too much room in the main bag. I'll probably get the Id and if I don't like how it packs in my main bag, I'll just use it for work.