reducing the bubble height should help with the wet/dry skimming. decreasing air will actually increase height, increasing outflow will decrease height (I think I got that right)
Also, if your skimmer is sitting right all the way in the water, ie; the collector cup's base is in the water... the raising and lowering of the skimmer relative to the water line will also affect the height...
But let me preface to say that I'm no skimmer expert and it did take me 2 weeks just to get mine working well...