I'm with LarBrd and others. Love's performance has suffered, but in all likelihood due to fit and system rather than a decline in ability.
He's 27 and locked up for money that will not look nearly as expensive by the end of his contract. (Think about how our view of AB's deal has changed).
He projects as someone who can give you a legit 20/10 with good 3 point shooting. His defense isn't great (or maybe good) but hey, people said the same thing about Ray Allen before he came here.
No, he's not a top 10 player. But he's a great second banana and a huge upgrade over anyone in our frontcourt now.
Crowder's a fan favorite, and has become a top 10 player at his position, though much closer to 10th than 1st.
Love is a perennial All-Star in the right situation, while Crowder will probably never make an All-Star team.
And the 20th pick in the draft - please. If that's a significant impediment to getting an All-Star in anyone's eyes, I don't know what to say. That slot often doesn't even yield a rotation player. We're talking Bruno Caboclo, Tony Snell, Evan Fournier territory.
We need to swap quantity for quantity and this is a great first step. Honestly I suspect it'd take something more like Amir Johnson PLUS Crowder plus a few decent picks (though not the BKN picks). But even that deal is a good one, we got AJ with precisely the goal of having him be a valuable salary/player piece in a bigger trade.
Get Love, make a power move for Horford, and swap our more valuable picks for a top-tier SF or SG, and you have a team. We have the assets to make that happen.
And if Love doesn't work out great, trade him to LA in a couple of years. He'll be up for that and still worth his contract, particularly to the Lakers.