Pillar rough comparables would be Billy Hamilton, Alex Gordon, Jacoby Jones. Hamilton was signed as a FA for the same money Pillar is making this year.
Pillar would be a minor upgrade on existing options for a team needing an OF. Entirely possible the next OF on such a team's depth chart delivers more than Pillar.
So basically, he's worth a bag of balls.
Now if the Jays eat a couple of million, they could get some value back.