Me thinks your problem lies with the silica wicks.  Once you go Koh Gen Do, you'll never look back.  I struggled with stock 
coils myself when I first started out. The flavors would often get better or worse within the same load. Once I learned to re-wick, a lot of the problems went away.  On another note, 
I found that anything above 1.8 ohms didn't really pan out with my Evics.  Speaking of which, I haven't used either one of them for a while.  Thanks to you, I think its time for a re-visit.