ORLANDO — In at least one area, the Giants are getting solid reviews for their early offseason work. They have put together a coaching staff that includes needed experience around first-year manager Tony Vitello, but also young coaches who have built strong reputations while coming through the ranks with other organizations. Throw in the additions of Bruce Bochy, Javier Lopez and Curt Casali to the front office, and Vitello and president of baseball operations Buster Posey will be surrounded by a group that looks well-rounded on paper.None of that will matter, though, if the roster doesn’t get better, and on that front, the Giants have been quiet. The only free-agent contract thus far has gone to lefty reliever Sam Hentges, who will try to join Erik Miller as bullpen lefties as he recovers from shoulder and knee surgeries. The Giants also have added some depth to their outfield, but their most notable offseason move thus far has been a departure. Marco Luciano, formerly their top prospect, was claimed by the Pittsburgh Pirates on Friday.That left the Giants with an open 40-man spot as they flew to Florida for Major League Baseball’s annual Winter...