ok, even though I just mentioned I didn't really want to add elements to the logo I will entertain #100. What if instead of the transparency that has been placed across it you tried the following:
-at the top of the circle where it is gray and goes down the right hand side, try doing a gradation starting with gray at the top and eventually being "almost" black at the bottom.
-then with the purple part of the circle that starts at the bottom see what it would look like to do a gradation from dark to light on the left side.
or you could also look at it another way...
-to top left quadrant of the logo is black, the top of the circle going around the right side gradates to gray by the time it was at the bottom.
-the bottom right quadrant of the logo remains purple and as the circle goes up the left side is gradates to lighter
-top right 2 bars could then be a gradated bar starting light at left and being full purple at right.
-bottom left 2 bars could be gray being lighter on right side and darker on left.