I said Ells + Cecchini first off.
Second off, Trumbo has a career .780 OPS. He has had 1 season with an OPS over .800 (this year) and it was .808, not like it was .970.
He's essentially in the class of guys like Justin Morneau, Freddie Freeman, Mark Teixeira, etc.
Not vintage Tex. Old Tex.
Getting a .305/.394/.433 guy who stole 50 bags and was a top 100 prospect per both FG and Keith Law along with Jacoby Ellsbury would be a solid deal in return for Trumbo, who, by the way, is hitting pretty consistent with his career numbers in the minors (.804 OPS), and never made a top 100 listing.
The league average OPS for 1st basemen last year was .777. It was .791 in the AL in 2011, .801 in the NL in 2011. In 2010, the league average 1B hit to a .812 OPS (NL), putting Trumbo's current season below league average.
So, overall, you're getting a slightly above league average 1B who has a swing that is perfect for Fenway. His numbers would be monstrous at Fenway, no doubt. But in terms of his value as is, playing in LA? It's not nearly as high as you try make it sound.
Ellsbury + Cecchini would be a good deal for him.