I can't imagine this will be a popular opinion, but let me state my case.
Danny Espinosa has been awful this year. Over 167 plate appearances, he's hit .158/.193/.272 with a whopping 3 home runs, and his strikeout percentage (28%) and walk percentage (2.5%) are miserable, especially when you look at them together. If that wasn't enough to make you roll your eyes, Espinosa is also the guy Braves fans love to hate because he stated that the Nationals were better than the Braves, even after getting swept in mid-April. And he's been so bad that Nationals demoted him and won't promote him for September. So what we have is a miserable offensive second baseman that Braves fans aren't going to like and that the Nationals don't seem to like, right? Wel ...
Espinosa isn't a great offensive threat and probably reminds a few too many people of Dan Uggla given the amount of strikeouts, but he's likely not as bad as this season indicates. The primary reason is that he's played basically the entire season with a broken wrist after Paul Maholm hit him with a pitch on April 14th. So the amount of credibility that 170 plate appearances of a mostly broken-wristed ballplayer probably isn't high, and given a clean state and clearance from a physician, I like his chances of rebounding.
Because before this train wreck of a season, the switch-hitting second baseman was basically an average offensive player, which is above-average for a second baseman. Espinosa won't hit for average, will walk a bit, and will hit for some power. Essentially, he's Dan Uggla-lite on offense - doesn't walk as much or hit as many homers - but it's close enough that he's worth having on the team. The high strikeout rate is a little worrisome because he's always struck out in over a quarter of his at-bats, but he does add some secondary skills to make up for the low batting average.
And while he might hit like a lighter version of Uggla, he doesn't play defense like Uggla. In fact, the bearded one is actually a very good defensive player, and he can play above-average to elite defense at second and shortstop - and probably third base if there was a need. Playing excellent defense is a valuable skill, and the fact that he can play both middle infield positions well gives him flexibility, which is something valuable.
Espinosa is also valuable on the bases. He was 37/49 (76%) in stealing bases during his two full and healthy seasons, and he generally gets good overall grades for his baserunning. Again, Espinosa might not hit like an All-Star, but he does add value in other areas that could make him a valuable player.
If you like Wins Above Replacement, Espinosa was worth 3-4 wins in each of his two full and healthy seasons, and that's better than what Uggla has been able to accomplish as a Brave. Add in the fact that Espinosa is 27 for all of next season, and we have a player coming into his prime that might not even reach Super Two status because of his demotion to AAA (and subsequent time off due to injury). Essentially, the Braves would get 4 years of a player in his prime who's been productive while healthy.
The additional advantage to the Nationals' second-baseman-fallen-out-of-favor is the flexibility it could give the organization. Want to trade Uggla? It would probably require the Braves to eat $15 million of the $26 million left, but the Braves could use the savings while still having a player about as likely to produce next season as Uggla. Want to trade Chris Johnson? The Braves would save about $5-6 million, and if Espinosa can play shortstop, he can learn to play 3B. Even if you keep both of those players, you can move Espinosa around to the infield positions to give players a day off while also having quality depth in case of the inevitable injury.
As for that little spat over the quote at the beginning of the season, I kind of like it. What else do you expect him to say mid-way through April? "Yeah, we suck. Let's give up." To me, it sounds like a guy sticking with his team, and at this point, I don't think he's very enamored with the Nationals anymore. If he comes to Atlanta, I imagine he'd bring that team attitude here. I don't see it as a bad thing.
So what would it cost the Braves in return for Mr. Espinosa? It would likely require a decent prospect, but considering the Nationals have destroyed much of his trade value with the lack of production and refusal to promote him for September, it likely wouldn't cost something the team couldn't afford to part with. I'm thinking a guy like Sean Gilmartin or Aaron Northcraft might do, but I'm just speculating - kind of impossible to know the exact price tag. The down side to all of this is, of course, that the Nationals are in the NL East, and I'm likely not the only one intrigued by Espinosa. If the Nationals have a comparable offer, they'd probably prefer to trade him outside the division.
As with everything, it all comes down to the cost. I see potential and a valuable hole on the team to be filled. But I'm not forking over a major piece of the future for him.