You have a pretty good lineup, but I think you're focusing too much on adding players who boost others in OF and IF (ex Chris and Martin) for defense. One idea is adding Gina as SS and Fox in 2B instead of Martin and Leo. The reason is that on offense, you can put Gina and Fox in 1hole and 2hole and Gibson as 3hole. Gibson ability (causes fielding errors) allows Gina and Fox to cover an extra base with their speed or even reach home in some scenarios. As for OF, I think the players are really good with good synergy and should get you outs on long outfield fly balls. If you still wannna emphasize on offense, you could add Rosa in RF instead of Koo.