TSN's pay site compiles ballpark stats for the year to date and the last three years. If you compare the stats from the 16 games this year to the other ballparks in MLB this year, Bithorn Stadium ranks 6th in scoring behind Arlington, SkyDome, Coors, Fenway, and Kaufman, with 11.56 runs per game for both teams.
However, it is at the top in home runs per game, with 3.9 homers per game on average. The next closest stadium for homers is Coors with 3.1 HR/game. For batting average, it only ranks middle of the pack.
Seeing games there on TV, these stats make some sense, because that stadium has a whole lot of foul territory, almost comparable to the foul territory in Oakland, and that can be expected to reduce batting average. However, the right and left field dimensions are much smaller than any MLB stadium, which would explain the homers.
Bottom line, a great place to start power hitters. For pitchers, it's a bit risky, but really if you'd start a pitcher at Fenway, Kauffman or SkyDome, it's probably just as safe to start them in San Juan.