Dominik is very fast, and he plays a modern right or left back (in the attack for much of the time). He normally does very precise crosses. Central defense is not an option due to his size, but he also makes a good midfielder.
I don't think he has to worry about playing centre-back. Having seen him play do you personally think he has a future, or is it unclear? Have you watched A-league, is he at that level?
I am a dad, and dads are normally not the ones you should ask about their son's level of play :)
Two ex-pro's from Austria thought he could sure play the first league there. I guess the A-league is not too far from that level (although better than the austrian league, I suppose). Some of his colleagues from Linz academy already play at first league teams, and I thought he was at least as good as them. Bayern also wouldn't pay for a player if they didn't think he had the potential for more than their reserves. But you know, young players need a supportive environment to develop (coach and teammates).