OT may be the way to go. Oliver Vernon deserves a change to develop and show improvement. So trading up for a DE is foolish, especially with this being such a deep class for the position. We little to none have young talent to develop that is anywhere close to starting (so don't name drop Yeatman or Garner) beyond Martin. If you get Lane Johnson, a beast of an OT who can play either right OR left, and an improved Martin than you are much closer to the athletic offensive line that JI wants. I'm all for trading up for Johnson or Dee Milliner.
The only instance I would want to trade down would be to grab Tavon Austin and Tyler Eifert at the top of the 2nd round.