You know who's not on this list? Michael Choice and his -1.7 WAR.
I'm OK listing just Mike Trout like 9 times and giving no other option. But I'd be not doing anyone favors not listing the other monster candidates right now. It's actually a very stacked list, and two viable monsters recently got hurt (EdE and Balco Moss).
Also not making the list but deserve serious props for their years so far: Jose Altuve, leading in hits and average and steals, and has as many doubles as strikeouts. He's like 4'5 and the coolest lead off man since the Man of Steal. Texas has lost a roster worth to injury, yet Adrian Beltre gets better and better like a fine wine with age. And Kurt Suzuki..top ten in average. Huh say wha..