Didn't read JRM's reply, so I may be duplicating things here!
Walker is your weak link on the hitting side. Lugo will be an improvement, but not by very much IMO!
I like Nevin in round 17, giving you solid backup at 2 positions.
Lovely starting pitching for a 14-team league, especially with grabbing Felix for the future. One more couldn't hurt, though.
Relief pitching, as you say, is your obvious weakness, although the three MRs are all quality. Eddie's injury problems worry me. But he may not be important in the scoring system your league has.
Overall, I like your team more for the future than this year, especially if you can snag two more top quality prospects. But I still think you can compete this year; you won't finish first, but you won't finish last, either!
Need some advice on this question, please:
http://www.fantasybaseballcafe.com/foru ... hp?t=90348