I used to keep all my blueprints in books, which lead me to looking at the empty slots, wanting to find new bps to fit in them. Recently, I TTed all the 'dupes' (believe it or not there was something like 17 ped in tt value just in the tt value of the dupe bps, lol) to clean up my collection, and moved all the bps in to boxes instead of books since the crafting terminals don't require books any more. I have to say, that it is very nice now not looking at all those empty slots. It does make finding the bps a bit of a hassle, but it takes a lot of stress out of the game as far as crafting goes since I'm now not on the constant search for the missing bps, which likely are all semi-rare and overpriced anyways. Also, this freed up several peds since all those books, each a ped a pop was just wasting peds that could be used in better ways.