Yes I agree. Although if I was going to bool out the cylinders, then I would have to adjust the thickness of the panels on both sides by the diameter of my cylinders before I do the construct Isect command so the pipes would actually cut a clean through hole!

I also rethunk the "Why 3d holes". A 3d Printer would be nice to have, Eh! Then you could template drill all the angle holes.

Anyway, this "slicing" has come up before and I think the couple tools you've provided here are a great addition in this area.