Organizing bookshelves by genre versus author

Now that I'm transferring my book closet over to the living room, I'm starting to weigh the pros and cons of different bookshelf organizing systems. I separate by hardcover and paperback for visual effects and wood spacing, but other than that, I've always done by genre then alphabetical order of author.

The problem I'm running to now since working on my personal library transfer into the living room, I'm getting confused on genre and wondering if I was doing it the best way before. Where I had divided bookshelves in the book room, now I'll have just have three large bookshelves. I started putting up the mysteries but started realizing how confusing it was. Which suspense fell under mysteries, and which fell more in with horror as a thriller? Which chic-lit blends with romance, and which blends with general fiction and drama? I always put the YA's together, but some of them are Urban Fantasy YAs and some of them are drama YAs. Then you get the blend where some of the YA's by an author were seperated from the author's adult works....same if they write in two genres. Eek!

Benefits of Organizing by Genre

  • Big one - Easy to go to the section when I'm in the mood for that genre. This happens all the time.
  • Easier to keep track of how large a genre section is getting. This helps to keep track of when I know I have a lot of unread left in that genre still and need to buy less of it.
  • If I can't remember an author but remember a book title or series, can find it faster skimming the genre section on the shelves.
  • If someone comes over and only likes one or two genres, it's a lot easier to show them what I have to read. 
  • You can divide into sub-genres - with my romance now, I divide into Harlequin, then Historical, then Contemporary. 

Cons of Organizing by Genre

  • Genre is confusing for so many blends - See red text above. So many books are too difficult to classify correctly.
  • When an author writes in more than one genre, or writes both YA and adult, they have to be separated on the bookshelves. That can irritate bibliophile OCD tendencies.

Benefits of Alphabetic Order

  • Can find a book right away, no matter what genre, if you remember the author's last name.
  • Author books will never be separated, even if they write in different genres, or if they write YA and adult.
  • No confusion on knowing what genre a book falls under.

Cons of Alphabetical Order
  • Some of the specialness is lost from sections if you have large collections you want to keep together that don't have the same author. For example, it can feel weird to have a big series of horror with a harlequin right after, but if you have a large harlequin collection, having the same sized novels and same cover spines together not only looks cool, but it makes sense.
  • Some series and such have different authors, so these would need to be separated. Eek.

Why other considerations aren't really considerations

  • Color - Pretty for Instagram shots but not useful at all if you have a large book collection with different genres. If you read one or two genres, it's not bad, and have one bookshelf....but once you hit a large number, read different genres, it's just too hard to find that book in the mountain of colorful spines. Impressive for company and a type of style where mixing hardcovers and paperbacks DOESN'T look bad, but then there's the issue of those books that don't have solid color spines.
  • Considerations like organizing by title make no sense to me - authors and series would be broken up!
  • Random books placed together with no order would be an absolute nightmare for my book collection and would disregard pretty much every pro point above for any of the systems.
Ultimately I guess I can't shake the genre confusion but will keep it that way. I'm too used to it. It's not perfect, but maybe the closest I'll come to it. Do you have a system that works for you?