Moving off of catcher is a difficult thing for me. At the Posey/Mauer elite bat level you want to maximize your performance both in terms of wear and tear and the total number of games played, but lots of big bats cannot catch, so keeping the ones who can there allows you to build a stronger lineup as a result.
Vazquez makes it harder because his defense is so elite at a position where we are only starting to get a clear sense of measurable value, and it is more than people had previously thought. Hoping that Swihart can be valuable as a corner bat seems reasonable, but you have to evaluate the long term value of three situations:
A) Vazquez C#1, Hannigan-type C#2, Swihart Corner
B) Swihart C#1, Vazquez C#2, Hanley/Pablo/Victorino/Betts/Napoli type Corner
C) Swihart C#1, Hannigan-type C#2, Hanley/others type Corner, plus the trade value returned by trading Vazquez.
You could also boldly reverse C and trade Swihart, but I will leave that out for now.
My issue with A) are, I don't think Swihart necessarily has enough offensive value to differentiate himself from the pack of corner types. Sure on the upside he means not signing a Pablo/Hanley and having that much more money to spend, but he hasn't yet demonstrated to be close to that level of offense.
My concern with B) is that we don't maximize value and end up sitting Swihart or Vazquez too much (Keith Law when asked this week about trading Vazquez said "Trade. Too good to be a backup. Both guys look like starters to me.").
My concern with C) is of course that we trade too low or too soon, and Vazquez goes all Yadi for another team, while Swihart follows the heralded switch hitter path of Salty and never becomes great.
So my thoughts would be on having them share time (B) when Swihart is ready, and hopefully have enough info after the first partial season of that to consider whether A or C is the better offseason option before 2016.
I also want to throw out there (potentially in Swihart's favor and to the detriment of Vazquez) that pitch framing value may have already peaked historically.
As umpires and MLB and analytics all have it pretty clear that it means "Duped the dumb umpire", the very reputation for being great at it will work against a catcher. When that happens the zone of "borderline" pitches that an umpire will judge based on catcher receiving mechanics will narrow, and some of the top "thieves" will potentially be even overtly or subconsciously punished on these by umpires not interested in playing the Washington Generals to the tricksters.
Maybe I am being slightly too optimistic that umpire pride in accuracy and zone consistency will outweigh the ghost of Eric Gregg, but it really seems to me that pitch framing as a skill is completely subjective to umpires playing along, and the more it is talked about, the more umpires will work actively to reduce it.