One of my favorite features in LR 5.3 is the radial filter. I use it to change photo lighting, especially on faces that have dark shadows. To me, it's easier in LR than doing it in PS. I also have quite a few presets and some favorite black and white looks that take too much time in PS. As April said, once you've made changes to one photo, it easy to apply the same change to batches of photos.
I do not use it to organize scrap supplies although now that it supports .png, I may try it in the future. I do prefer a file organizer that I can use to browse my file folder structure over Lightroom's process of having to import.