You lost your best pass-rusher and picked up a shitty injury prone guard in Cooper who has lost his starting job each of the last two seasons due to very poor play and was being moved to his third position on the o-line in Arizona. He's basically a non-player at this point.
The 2nd round draft pick is a late 2nd round pick. 61st. You better hope you guys draft well this year
The only plus of this is cap room and as you probably would have lost Jones for only a compensatory 3rd round pick after next year anyways. Cooper sucks. A lot. You have wiggle room though, for all your free agents needing new contracts after this season.
But boy oh boy, your D is going to suck rushing the passer this year without bringing in some major help and no, a washed up, old, oft-injured Chris Long doesn't count. 
The 2nd round draft pick is a late 2nd round pick. 61st. You better hope you guys draft well this year
The only plus of this is cap room and as you probably would have lost Jones for only a compensatory 3rd round pick after next year anyways. Cooper sucks. A lot. You have wiggle room though, for all your free agents needing new contracts after this season.
But boy oh boy, your D is going to suck rushing the passer this year without bringing in some major help
and no, a washed up, old, oft-injured Chris Long doesn't count.
Chandler Jones is a very inconsistent player, who never reached his potential with the Pats. Injury-prone, pads his stats in bunches vs weak teams and disappears vs good-not-great LTs. He is a good player, who can make plays but not a difference-maker and certainly not better than Ninkovich or Sheard, who he kept losing playing time to in the final 3rd of the season and the play-offs.
Considering how Vernon just blew up the DE market, Pats would have never kept Jones as he'd have asked for way more than he would ever be worth to the Pats. So, Pats traded a one year of Jones for a one year of Long, Cooper, a valuable 2nd round pick and cap space they would use in extending Hightower, Collins, Sheard, Butler.
Long may not be the player he was 3-4 years ago but has finally gotten healthy and who knows - even at 85% of his old self, he'd be close to what Jones offers. He is a DE who plays the run great and that's a rather underrated stat for the position as pwople tend to over-focus on the sacks. He is an excellent fit for Patriots' defensive schemes and that's what Pats do - acquire players on the cheap they can put in a better spot to show their best.
Cooper has had his growth stunted by injuries at Zona but he is still a player the Pats had as the 5th best prospect, overall, in the 2013 draft and with Scarnecchia coming back as OL coach, sky is the limit for him. Worst case scenario, they lose him after a year at a portion of Jones' cap hit.
That pick may be 61st but Pats don't have a 1st rounder this year, in a draft where a late 1st round pick (where Pats usually pick) has about the same value as a late 2nd because of the lack of quality in the draft beyond the top 15-20 players. A pick, Pats could well spend on a quality DL prospect, given this is the best/deepest position in the draft, to replace Hicks/Jones. A player they'd have for 4 years on a 2nd round rookie deal.
If you ever wondered how the Pats manage to stay at the top year-in, year-out in the cap/FA ere, look no further than deals like this one or when they traded away Mankins, 1.5 years ago - plan for tomorrow, don't get caught up in the yesterday.
P.S. btw, rumor has it, Packers were one of 5 teams that inquired about Jones. Other than Zona, the other 3 were Cleveland, Jags and Atlanta. So, count your blessings Ted T didn't get stupid 'cause the only way this trade would be good, to any extent, for the other team is if they end up extending jones on a 15 mil APY deal after 2016, which winning teams generally don't do outside franchise QBs.
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