There is no way that package is good enough to get Cousins.
Any package for DMC is going to likely need at least one probable top 5 pick. That is in addition to a high level prospect (i.e. Marcus Smart). I don't we think we have any pick that is likely to be in the top 5, so I don't see Boston as a realistic trade partner with Sacramento.
It's not a bad package. If Cousins demands a trade and is only willing to go to a couple teams (Boston included), that deal could possibly happen.
The Kevin Love deal was unprecedented. Just completely crazy-town. Under normal circumstances, you don't trade a potential superstar #1 pick for an all-star with one year on his contract. That never happens. It made some sense in context of LeBron James going to Cleveland, but that in itself is a pretty unprecedented situation. Look, I'm one of the most blatant pessimists here, but even I know we can't look to that ridiculous Kevin Love trade as setting the market on trading all-stars. When you get out of crazy-town, the semi-recent hauls received for Melo, Dwight, Chris Paul and James Harden should be looked at.
The rising cap throws an interesting wrinkle into it, but it really just depends on how big of a stink Cousins throws... if he throws one at all.
I'd like to assume that the Knicks would give up their top 4 pick, but they could just decide to build around youth and trade Melo. I'd like to assume that Philly would make a compelling offer for Cousins, but they might rather build around the young core they have. Perhaps the Timberwolves would give up their top 5 pick... but why not just build around Wiggins + Towns/Okafor? Maybe the Lakers give up Randle or their pick... can't rule that out, but who knows what that team will do. I'm sure teams would have compelling offers. Marcus Smart + Bradley + Sully + #16 + #28 + Brooklyn's 2016 1st seems like a nice starting point in an offer that will at least get Sacramento to pick up the phone.
This does, however, confirm my belief that if Boston has any hope of landing a star this Summer, Marcus Smart is probably the most likely to be traded simply because of the urgency to land star talent and the simple fact that no team in their right mind is trading for a Boston pu-pu crap platter without at least getting Smart. Smart is a B- asset in a sea of C's and D's. Gotta give something to get something.