Anyone know of a method or extension to delete overlapping paths? In this particular case, the shorter of the two paths. In some of my designs, I might have hundreds of these overlapping lines. Deleting by hand is not a solution. I believe Lightburn has this capability?

I have come across this extension: https://inkscape.org/~EllenWasbo/★remove-duplicate-lines-with-tolerance but was not successful with it.

This extension might help you.
https://inkscape.org/~jgk/%E2%98%85cut-and-remove-by-shape-extension

I've also used this in the distant past.
https://github.com/funnypolynomial/DestructiveClip

And here's an old related post.
https://inkscape.org/forums/questions/cut-path-and-then-delete-lines-not-covered-by-cutting-path/

Thanks - 
Something that has been jinxing me for a long time. I would imagine something to do this would be very complex to code. Would have to break paths down to sub paths and compare them to each other. If I find a method - will report back. 

Side note - this extension works perfectly for removing duplicate nodes. Use it quite a bit.
https://inkscape.org/~EllenWasbo/★removeduplicatenodes
 

Path > Union almost does all of the work for me. Does it beautifully too. If I can figure out how to add the red diags. Will play around with those extensions you mentioned. 
Duplicate the original. Take one copy and union it. Grab both copies and apply that extension. Hmmmm - maybe? lol

Edit: Tried the extensions. Nope. The following method seems better than node editing. Yuck.
Note:The deep ungroup is to correct a behavior of combining nested groups of objects/symbols. You end with a freaking mess with the resulting combine buried in a stack of empty objects (no path data).