Fantasy Baseball: Keeper League Trade Offer

Got a trade offer recently and thought I would get a little feedback from you all.

In this keeper league (you can see details and my team here:  http://www.faketeams.com/2010/3/26/1391392/keeper-league-draft-results

I was offered the following:

I give - Justin Verlander, Jason Heyward, and my 3rd round draft pick in 2011 draft

I receive - Adrian Gonzalez, Jacoby Ellsbury, Jenrry Mejia

Given that my team is very nicely set up with good pitching, this makes Verlander a bit dealable.  I hate the idea of giving up Heyward (gave up Josh Johnson, Ross Detwiler, and a draft pick to get him around this time last year).  I already have Prince Fielder as my first baseman but having another big bopper will never hurt (especially having 2 of the 4 guys who hit 40 or more homers).  

My outfield has Jay Bruce, Heyward, Cameron Maybin, Alex Rios, and Juan Pierre currently.  Ellsbury would be nice add to this (Minus Heyward from the deal) and give me a nice trio that can help my SB category but really leave me handicapped in the power area in the OF.

Mejia would just add to the studs that I have in my minors team.

Do I go for the deal or work on building my offense through smaller deals and young guys (Jesus Montero and Mike Stanton waiting in the wings in my minors team).

Thoughts and comments are welcome.