Te combo doesn't quite work for me, but it doesn't have to. If you like it that's what counts. As someone else noted, the top of the lower barrel needs to be turned down more. I actually turn the top of the lower barrel below the bushing so that it meets flush with the flat part of the coupling. That way you don't see the top edge of the blank.
Try this once to see if you like the effect - Turn the top of the lower barrel flush with the bushing. Then swap the cap bushing in place of the coupling bushing. Now, take the blank down about 1/3 of the way to the cap bushing. After assembling the pen compare it to what you do now and see which you like best.