......Not sure if this is the right forum for this type of chat, but I made a big improvement in both of my Kayfun lites. They work so great now that I will share what I did!
Months ago, I increased the air inlet hole to 7/64" and yes, this created a somewhat more airy draw. But it still was a bit too restrictive. And I would get dry hits when I chain vaped. I did some research. I read somewhere that drilling the air tube helps just as much, so I used the same 7/64" drill and opened up the main air tube hole as well as the holes that go across and through the hollow tube. {7/64" drill again} -Finally, I chamfered the air hole up by the coil.
I also took a dremel and made the two vertical juice channels just a bit deeper. Nothing major here, but my FastTech Kayfuns looked like they were machined a little light in this area.
These changes make these attys wick fantastic, and the draw is airy enough to lung hits easily. I NEVER get dry hits anymore, or flooding for that matter.
Sorry if this has already been discussed but this thread is just too massive to completely read.

-Happy vaping to all of you!