In fact there have been some books about UI in LabVIEW. Simpler is usually better, originally there was an attempt to make LabVIEW UI's look like actual instruments, which wasn't a bad thing, Tektronix and HP (now Agilent) as well as others had done tons of work making their interfaces work well. Now there seems to be this "make it look Windows like" move among some, which I'm not sure is optimal, particularly, like which version of Windows? While some other User Interface software makes it easier to do the "cool" stuff, like automate tanks filling/draining, showing motors running or flow through pipes, it can, for the most part, be done in LabVIEW. There have been a lot of papers on the subject as well
http://zone.ni.com/devzone/cda/tut/p/id/5319 or
Tomi Maila's blog that discusses LabVIEW UI design
PutnamCertified LabVIEW Developer
Senior Test Engineer North Shore Technology, Inc.
Currently using LV 2012-LabVIEW 2018, RT8.5

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