I've actually got a very similar issue that will be facing me shortly in my dynasty league. I have the 4th and 17th picks in the first 3 rounds. As someone who has the first pick, you obviously get your choice of anyone in the draft. MLB.com revised their
Top 100 Prospects at the end of the season, and several '12 draftees made the list. Jose Fernandez is listed at #22, so he should probably be your first priority. But of everyone from the '12 MLB Draft, Byron Buxton is rated the highest. Here's the list:
Buxton - #28
Carlos Correa - #34
Mike Zunino (Sea - C) - #44
Albert Almora (ChC - OF) - #45
Max Fried (SD - LHP) - #54
Kevin Gausman (Bal - RHP) - #56
Kyle Zimmer (KC - RHP) - #61
Delino DeShields Jr (Hou - 2B) - #77
Addison Russell (Oak - SS) - #89
David Dahl (Col - OF) - #94
The two Cuban prospects are both on the list as well, with Jorge Soler (ChC - OF) listed at #69, and Yasiel Puig (LAD - OF) at #92. Jesse Biddle is also on the list at #75. Personally, I'm hoping Zunino or Fried/Gausman fall to me at 4th. The MLB.com list has ETA listings for each prospect, and Zunino's is the soonest, 2014. My team is in the dumps so I'd like a talent infusion sooner rather than later. Fried and Gausman are both very intriguing and I'd be happy to land either of them as well. For you, I would definitely grab Fernandez first. It's easy to rank new guys high when they've yet to prove themselves, but someone who's remained high on the list after a full season is worth more IMO.