Reasoning on Presumed Plan : Wilson Ramos in 2011-2013 put up good offensive numbers when in the lineup. They may not be that impressive in comparison to the league as a whole, but in comparison to other catchers they put Wilson in the #5-#10 range. It's that talent, particularly the 20+ home run power, that the Nats want to keep in the line-up. Wilson is still on the right side of 30 (will turn 28 next August), and is cheap and won't be a free agent for 2 more seasons. Wilson's defense is debated but it's certainly not terrible. He's decent behind the dish, and has got a good enough arm to throw guys out. His biggest issue is the hot stat for 2014 "pitch framing" but even though he's below average he's not close to the worst in the league.
Lobaton makes a good back-up for Ramos. He's slightly better defensively with better pitch framing skills being his biggest draw. He bats both, but is better from the left side. He's played 235 games in the last 3 years, so he's able to play a lot of games and it not be an issue for him. He's cheap, not being a free agent until after 2017, and he'll be 30 next season which isn't an age you'd expect a break-down of skills, even for a demanding position like catcher.
As for any other internal options. Jhonatan "Don't call me Johnathon" Solano finally hit a bit in AAA but showed nothing in the majors and at 29 next season is too old to be any sort of prospect. Sandy Leon is still kind of young, but hasn't hit in the minors yet (relying on patience to get the OPS up) and is more of a defensive presence. The Nats have an intriguing catcher prospect or two (kieBOOM!) but they are in the lower minors and not ready to make an impact, even as a back-up.
Problems with Presumed Plan : Going with Wilson Ramos is iffy. The guy eeked out a half-season last year and that was the most he had played since 2011. You can't expect more than 100 games from the guy and you have to accept the real possibility the guy misses 2/3rds of the season. These injuries have a ripple effect on the line-up where Lobaton, a lesser bat, is forced into every day service and a complete black hole of a hitter like Solano or Leon kills the 8th spot in the order every 4 or 5 days.
Of course that's assuming Ramos' hitting holds up. His offense took a bit nosedive this year as his power dropped down to the lowest levels of his career and he's stopped taking any sort of walk. Scale up the homers to 140 games and it's 17-18 where he hit 16 in just 78 games in 2012. Eventually injuries do take their tole and at a spot like catcher those nicks and dings can be magnified. If the power goes the Nats are left with a .270 singles hitter. A SLOW .270 singles hitter which means they can expect a lot of double playes (his 17 this year were good enough for 13th in the league despite playing only 88 games)
As for Lobaton it seems likely that the average 2012 season he put up for Tampa was the peak of his career. Nothing else that he has done in the majors suggest a good hitter of any sort and he's at an age where things may not collapse, but they are probably trending down.
My take : What can you do? There is one good catcher on the FA market this year in Russell Martin. He can hit and he can field. He's going to cost someone alot with a contract that'll extend right through his decline years. After that it's Geovany Soto (ok hitter, bad defender) or taking an flyer on Nick Hundley (a couple bad offensive years, good defender). In other words there isn't an easily available better option than Wilson Ramos. There also isn't a cheaper younger FA back-up you like more than Lobaton unless you are trying to find a pitch framing star. The Nats are basically stuck with what they have unless they want to trade.
What they have isn't terrible, though. You can still hold out hope for Ramos, at least for one more year. It's quite possible his bad year overall was because of not being 88-game ready thanks to all those recent injuries. He really tanked in Sept (.203 / .221 / .297) but was hitting as well as .292 / .329 / .438 deep into August. I'd expect next year he can give you a decent 100 games. Of course the Nats want him to play 120-130 so there may be another late-season swoon on the way but I'd take a good hitting catcher for 5/6ths of the season. Lobaton may be on the downside of his career now, but I'd expect a mild bounce back from last year's performance if someone can get him to just pay a bit more attention to getting on base.
Ramos and Lobaton and pray for health. Not great, but probably better than more than half the league.
Outside the Box Suggestion :
Ramos' trade value is shot so trading for a good player in return and then signing Martin is not an option. And good catchers are an even rarer commodity so a straight up catcher deal for a decent catcher is again not going to happen. Even looking at it a round about way - say trading from a Nats strength like the rotation, it would be tough to find a decent catcher that could get dealt. Posey won't. Gomes and Mesoraco are too cheap to deal even for a good pitcher. After that you get into guys you shrug at. Probably better, but probably not that much better than healthy Ramos.
An interesting possibility could be Lucroy who's got two more years before FA probably takes him away from Milwaukee. That's the kind of contract the Nats like. But to get him would probably take more than a good pitcher (like Wisconsin native ZNN) because of the impending FA. Would you be willing to give up say ZNN and Cole for Lucroy? I don't think so.
You're best bet for an outside the box idea then is trying to deal him straight up for another catching prospect that hasn't panned out yet. A challenge deal of sorts. The two best bets there are Hank Conger (Chris Iannetta is the #1 there) or Tony Sanchez if Russell Martin returns to the Pirates. Not a great plan I know but unless you are insane and think Bryce can move back to catcher, it's the best I got.