It appears to me that Austin Martin has graduated to the major league level this year and that is good for him. However, I see a pretty limited upside. First and foremost, he plays two positions acceptably--second base and left field--not exactly the most vital defensive positions. He's played quite a bit of center field and he's definitely below average there. Secondly, as an offensive player, Martin lacks power. He has one homer in 214 plate appearances, although the 14 doubles and a triple give him an acceptable 16 extra base hits in those PAs. He's fast, but not a burner who can change a game or an inning solely by getting on first. Martin's throwing arm has been regarded as below average, limiting him to second base on the infield and precluding him from playing right field in the outfield. It makes center field more of a stretch as well. I don't know if his arm can or will improve, but I do know that making accurate throws (hitting the cutoff man etc.) makes up for a lot of not having a cannon like Matt Wallner.
I think injuries and lack of experience have hindered Martin's development, particularly as a defender, and that with better angles and fundamentals most of his rough spots as an outfielder can be polished up. With gradual improvement as an offensive player and notable defensive steps, Martin could be much better next year and step into a role where he gets regular playing time, perhaps being the alternative for Byron Buxton in center field as well as getting playing time in both left and second. I don't foresee stardom unless both his defense and offense have another gear.