I also have a backlog, and its also across platforms... Always is tricky, but I think what you should do is put off expanding your collection for now and play the games in whatever order YOU WANT. Don't choose all from 1 platform, or alphabetically. Pick one that appeals to you and give it a shot.
Play longer than you anticipate, and it may "hook you" too :P
I also find knowing someone who plays or has played said game is also a plus as you can discuss it with them and possibly become more motivated to finish the game.
Also, time is a serious commodity, you can always play the games at a later stage in life when things chill a bit (same problem here)..







