i am really not sure if this could be your problem, i am looking at my wick&coil set-up and seems the same. my wick is just below the pp, and my last coil is just below top of wick, maybe 1/16 of an in. i dont think its all that good if you have alot of space from top of wick to last coil, for the top part of the wick is wicking with no purpose. if may just be the fact that the wick is simply not broken in yet and not having its full wicking capability as of yet.
lol, I just forgot to take the fill screw out. I left it in because I was breaking it in with one of those tiny usb passthrough devices so I wouldn't have to drain my batteries and be able to lay it down on its side. Now the real question is, should I just pour out the half tank of not so good dekang juice out and fill it in with something more proper? Or soldier it out and vape it until its bone dry?