Moore seems much less athletic and toolsy than a Martin though. He steals bases more from pedigree than speed and that might not translate at upper levels. He is a nice prospect to have of course with 2 more years to prove himself before rule 5 eligibility.
This trade was all about the 40-man roster and the Phillies just feeling they can do better than Dunn. Almost everyone on the roster needs to play. At most teams can afford 2 or 3 younger prospects that are not quite ready (like Rojas when he was initially put on the roster). Everyone else needs to play. Castro will be our 27th man and the team likes him more than Dunn apparently. All the relievers with options will rotate through our roster throughout the year.
40-man rosters spots are just precious with a 26-man active roster and rising pitching injuries. Carlos De La Cruz is a prospect they like I am pretty sure. They just don't believe he sticks on a major league roster now because he is not ready.