Very nice, I'm glad you shared. I had a hobby project with the same problem but I took a different approach optimizing for search and retrieval using a Raaco storage cabinet which takes up a lot more space but you have the resistors more easily accessible. It does requires a lot of work folding all the 'compartment papers' so not for the faint of heart. The main benefit for the resistors is that you don't have to take the entire strip out, just cut the resistors loose while they are still inside the drawer.
https://github.com/tonybjorkman/raaco-organizer
I think using existing 'card binder'-sheets would make your solution even easier to make. And adding tabs would make search quicker. I will keep your solution in mind whenever there is a need to catalog large number of flat items, especially if I need to save space or move them around.