what kind of filters? the stackable ones? +1,+2,+4,+10 ?? Totally missed the focus here.. maybe play around with your Fstop? I do like the framing though.
In the first, your focus ought to have been on the eyes, and it slipped (you may have moved out of focus ever so slightly upon taking the photo), DOF is extremely (!) shallow with any means that are not a dedicated macro lens and you normally need more than oodles of light. I've tried the reverse lens method years ago, and while I was lucky with a few of my pics, I wasn't with most others!
You did nicely on the wing detail in 2, though in that photo I deplore the fact that in order to capture said wing detail, you cut the dragon fly (?) in halves, part inside, the other part outside your frame.