I've been using block diagram cleanup extensively over the past year in an attempt to speed up my LabVIEW programming. I am definitely faster as a result of using the feature, but there are still some VIs that I have to arrange myself, because diagram cleanup's arrangement is unacceptable. So the feature still has a ways to go in making all my diagrams acceptably clean. It's my understanding that there are many more configuration options in diagram cleanup that could potentially be exposed to the user, but I think an easier way to conform diagram cleanup to my standards would be to point it at a folder of VIs that I have personally deemed "clean", and have diagram cleanup mimic the arrangement in those VIs when cleaning up other VIs.
As an example, I am ok with input tunnels into a case structure overlapping somewhat, if those tunnels are coming straight from subVI output terminals that are close together. Diagram cleanup insists on adding space between the tunnels so that they don't overlap, which results in unnecessarily crooked wires. Ideally, I would have VIs in my "clean" folder that have slightly overlapping tunnels, diagram cleanup would discover that I'm ok with this, and subsequent cleanups would allow this arrangement.
