Forbes just came out with their rankings of the most valuable teams in baseball, and the Nationals come in at a pretty respectable 16th. If you're into numbers and math and all of the things that forced me to take a semester off from college, then I recommend checking the article out.
↵The most interesting stat for me is player cost-to-win ratio, which measures how much value they are getting out of their team relative to other teams. The league average is set at 100, and the Nationals scored a 98. So the Nationals got 2% fewer wins than their payroll would normally dictate. So even though a small payroll may be hurting them, it doesn't help that the players they do have aren't living up to the value of their contract.
↵But the Nats do have some things going for them. A beautiful new stadium, young phenoms Stephen Strasburg and Bryce Harper, and a fan base with room to grow. If they can start winning more consistently, they might move up this list a little bit in the future.