These are significant hires. Bennett worked for the last two years as the Astros' scouting director and previously worked as their farm director. He was dismissed earlier this offseason. (And yes, it's the Astros, whose interest in their minor-league system under Drayton McLane was notoriously nonexistent, so insert your own punchline, but those are high-level positions, and the team's drafting last year wasn't a joke at all.) Berroa worked for 15 years with the Marlins as a scout and as director of their academy in Puerto Rico. Hopkins was the Rangers' scouting director for five years before serving as a special assistant to Jon Daniels. He worked for the Orioles this year was but let go because of "philosophical differences" with scouting director Gary Rajsich. Kosciak was an area supervisor for the Astros last year; he evidently signed No. 11 overall pick George Springer in 2011.
Bennett and Hopkins, in particular, appear to have very significant resumes, so it appears the Pirates are serious about addressing potential problems with their scouting. Note that these guys were hired as pro scouts, however, not amateur scouts, so they'll be scouting players who are already in the professional ranks.