Sano. Mauer only has a couple of years left, and he costs $23MM per year. Sano has "easy power", and can play 3B or RF or 1B for most any team in the league in 3 years. Second choice for me is Gibson....you need 5 starting pitchers, and he has a legit shot at being a number 2 pitcher, though 3 is more likely. That is a super valuable asset, and he is much closer (meaning more likely to reach his potential) to the majors than Buxton. Buxton would be my third choice, but he's all projection at this point. That might change after this year, if he is successful and lives up to the hype, but I'm big on seeing production at a high level. Mauer, while clearly one of the best players in the game, at a premium position, is just too old to start a team around, imo. Also, those other players are more likely to have trade value, if you later want to start your team again, or upgrade your team. I think Mauer is awesome, I just would not start a team with him due to his age.