Some more "foreign" book porn, with a bit for those who like lists

Below are 6 pictures I took of my non-English, (mostly) non-Spanish book collection.  Somewhere in the neighborhood of 50 books in Portuguese, Serbian, Italian, Latin, German, French, Romanian, Polish, and Greek.  I made another post of two bookcases challenging people to discern a pattern.  This time, I think there are two easily discernible patterns.  Does having such patterns make it easier to follow the books, or is that merely an accident that some people write off as having a "purpose"?  Anyways, the pictures, for those who may be curious: