Stowers, Cowser, and Kjerstad all have "something to prove," this spring none of them really set the world on fire with their ML at bats last year. Heston at least held his own at the plate for his 30 ABs, Cowser to me looked particularly lost at both the plate and in the field.
I agree that Stowers is the guy most likely to be moved, because there just isn't a place for him, though I think he will need to have a good spring training to garner significant interest.