Detachable Cable + adapter cable
The only issue with your attachable microphone is the added cable. Having two cables dangling off of your headphones is just messy and a pain in the behind!
First, make the cable detachable using a standard 3.5mm jack that will also carry stereo audio, left, right and mic like in most cell phones. (TRRS).
Second, build and sell very short adapter cable for the most common headphone connections, 3.5mm, 2.5mm and mini XLR to connect the headphone to the microphone, and therefore only having to deal with one cable hanging off of the headphone/microphone.
Sure this would only work with headphones that have a detachable cable in the first place, but most hi-end headphone do feature detachable cable.
Also everyone with a super rare headphone connection can easily build their own adapter cable. A proper connection option on the microphone is vital to do that.
The mic can still be removed easily, and it is still possible to use it with the two cable configuration. This would make an already great product perfect and very versatile.
I hope you like my suggestion, I would love to see this product in the future.
Regards from Ireland,
Michael Lindsey commented
I'm thinking of doing this myself if there is no official support/product soon....really want this.