Tough being a Nats fan we have 0 players to pick from in ATG.
But that is not strictly true. The Nationals franchise goes back to before they were in Washington. Just because the team moved does not erase it's history. The Giants are in SF now but guarantee SF fans still consider what Mays did in NY to be part of their history? You think they do not consider Mel Ott to be fair game. Think Dodgers are not going to claim Gil Hodges, etc.
The Nats absolutely have a history. Perhaps the younger fans do not claim it but they should.
Don't be bashful about claiming Gary Carter, Galarraga, Grissom, Walker, or Vlad. Let's not forget pitching: Pedro, Steve Rogers, Mike Marshall, Wetteland, etc.
Maybe not the history and depth to challenge Yankees in most franchise leagues but they are represented in ATG.
Walker should be dominant 2015 set. But if 2015 is added, unless he gets derailed by injury or drugs so should the next 10 years. But you cannot give him 10 cards in ATG when so many HOFers are only represented by a card or two. Need to wait until retirement so we can look back with respective and select the top season or seasons.