I like your assessment of LabVIEW. I find that if your code is turning to spaghetti, you're not using enough sub-VIs. Try to find blocks of code that accomplish one thing and put that code in its own VI. As a bonus you get to design a little icon for your new sub-VI. :)

Your "rabbit hole" analogy is spot-on and I'm not sure how NI can address some of those problems. Some things like Ctags that are so valuable in text-based languages just seem to have no obvious analogy in a graphical programming language... it's fun to imagine though.

(Caveat, chemist talking about programming)