Here's what I think the Patriots will be doing with Jimmy Garoppolo.
First off they will not be trading him. The Patriots know what they have in Garoppolo and know he's both great insurance for 40-year old Tom Brady and also potentially their QB of the future. New England is the defending Super Bowl champions and their roster has actually gotten better this off-season. There is nothing a trade of Garoppolo would bring in return that would be more valuable to the team than what Garoppolo already represents.
The first two rounds of the NFL Draft are normally where teams find immediate starters. The Pats don't have any starting roles that really need to be filled. Maybe there's also no players that Bill Belichick thinks are worth trading into the first or second round to obtain either.
The third round on is where teams normally find roster depth. The Patriots are already a deep roster and they have picks from the third round on. No need to trade for "assets" here.
Now I've seen multiple sportswriters suggest that if New England wants to keep Jimmy Garoppolo after 2017 - then they "franchise tag" him after next season. I disagree with that view. Instead why wouldn't Bill Belichick offer Garoppolo a first round tender just like they did for Malcolm Butler?
If someone gives him an offer sheet then the team has the option to match it. Chances are great that the offer would be for multiple years at much less money than the franchise tag price. The teams who are most likely to make an offer are also likely to be the worst teams in the NFL with high first round draft positions. The Pats would then have the choice of matching the offer or getting a high first round draft pick which is more or what they could get if they traded Garoppolo today.
I could be all wet but this is what I see the Patriots doing with Jimmy Garoppolo.