I don't really see a candidate for a long-term extension at this point. Not really into a long-term commitment to Sanchez (or Stroman for that matter) with 4 years of team control left. Pitching is too scary. I don't really see the urgency to commit to Travis before we know what he his. Big questions about his health and about how good he really is.
People have thrown Pillar around as a candidate, but we already control his age 28-31 seasons. I don't think I want to commit to his age-32 season, 5 years in the future, when he can't hit and relies almost exclusively on his legs. Defense doesn't pay in arb anyway.