Cash,
I've been using the passthrough for 2 weeks now so I may have fresh perspective on the device. First off, it's a great device. If it got lost, run over by a car, stolen etc, I would feel a sense of loss and buy another one right away. That opinion formed just after 2 weeks of use. I may be in the minority but I do like the cable and its thickness was the primary reason why I looked into the device. Yes, it's ungainly and takes effort to get coiled up out of the way, but I see it as a necessary evil. It provides the current needed to dump out the billowing clouds the product is known and praised for. Also, the flexibility of the device to use a variety of atomizers sets it apart from other products.
Some thoughts on how the device can be improved (many are wishful thinking):
juice delivery mechanism - Becase my laziness should be overcome by someone elses inventiveness. I know not possible with the number of different atomizers supported.
Improved threads - on the body and adapters. It may just be the adapters and body I received which cross threaded a lot and dissimilar metals with one being softer, had a tendancy to strip the other.
LED - I know its a pain, but im a sucker for shiny objects and flashy lights. Besides, lets me know when the thing is activated, intentionally or by accident, the latter of which can be a bad thing.
Swivel - speaking for myself, I find that with the cable angle and stiffness the button locates randomly around the device axis and I have to hunt around for the button by feeling around for it. A swivel connector can orient the button where I want it, say my thumb, on demand and consistently. Something functioning like this perhaps:
Wider adapter channel - Its currently a minor/small pain to cleanout the trough in the adapter from gunk and juice that collects in there. My q-tip doesnt get in there just right to clean it real good.
Different colors - yeah I know, but a metallic blue would be kind of cool with the brushed aluminum trim, woudln't it?