Grandal might be biggest upgrade for these teams

For the entire offseason so far, all of the oxygen in the room surrounding the catching market has been sucked up by the never-ending J.T. Realmuto trade drama. That's not hard to understand, because Realmuto is very good, and in a down cycle for catchers, he's probably the best all-around backstop in baseball. Based on reports, he'll likely be traded this offseason.
The problem is, nothing's happened, because Miami's demands are reportedly exorbitant. The Mets got fed up and moved on to Wilson Ramos, other teams may be doing the same, and this all seems like a great time to remind you: Hey, remember Yasmani Grandal? He's available, he's just about as good as Realmuto, and he'd cost only money (and a Draft pick), not prospects. 
That this requires repeating is obviously due in no small part to Grandal himself, because he was unavoidably lousy in October, hitting only .138/.265/.276 and getting benched thanks to some high-profile defensive miscues. It was a bad look on the biggest stage, and it's probably having the inverse free-agent effect to that of Joe Kelly, who almost certainly rode a fantastic postseason into a third guaranteed year on the free-agent market.
That said, we ought to know enough by now to know that postseason performance doesn't do much to predict future performance. No one's ever going to complain again that David Price "doesn't know how to win in October," and no one really gave National League Most Valuable Player Christian Yelich a hard time for hitting .194/.383/.389 across two playoff series this October. 
If you can get past those bad few weeks, you can see just how valuable Grandal is -- and how many teams could desperately use him. Let's break it down.

Grandal was as good or better than Realmuto in 2018
Look at these two batting lines, won't you?
531 plate appearances, .277/.340/.484, 21 home runs, .353 wOBA, 126 wRC+
518 plate appearances, .241/.349/.466, 24 home runs, .352 wOBA, 125 wRC+
Don't get stuck on batting average. These are two lines that are just about as identical as they can get, to the point that it almost doesn't matter which line belongs to which player. (Realmuto had the first one, Grandal the second.) While neither steals bases (three for Grandal, two for Realmuto), advanced base running metrics consider the slow-footed Grandal a negative on the bases (minus-six runs) while the relatively speedy Realmuto adds value (plus-5 runs). It's enough to give Realmuto the edge here.
But the difference, of course, comes behind the plate. Realmuto is a perfectly solid backstop, one who owns the fastest pop time in baseball (1.90 seconds). While that's nice, it's arguable how valuable that actually is, since stolen base attempts keep dropping and dropping in modern baseball. While you'd expect to find that Grandal had a much worse time preventing balls from getting by him, that's not really true; he had 40 passed balls/wild pitches in 2018, while Realmuto, in 86 fewer innings, had 42.

We're going to pitch framing here, of course, and that is an area in which there's a massive difference. Over at Baseball Prospectus, they keep track of such things, and the results couldn't be clearer. Grandal was the best pitch-framer in baseball, adding plus-16 runs of value. Realmuto, on the other hand, was essentially league-average, neither good nor poor.
This has long been a skill of Grandal, who has ranked at or near the top of these lists every year. Remember back in 2015, his first year in Los Angeles, when Zack Greinke was pushing towards a 45 1/3 scoreless inning streak? Here's what Greinke said to the Los Angeles Times about Grandal, who caught every Greinke start during that stretch.
"He's been unbelievable back there," Greinke said. "His catching is better than advertised, and working with me individually, he's been as good as you could expect. I don't think, from what I've seen so far, you could ever have expected anything more."
"I couldn't draw up a better catcher at the moment."
That's high praise. It seems like people sometimes have a hard time understanding the value of pitch framing, and that's because it's hard to see it. That is, if a catcher lets a pitch go to the backstop or airmails a throw, it's pretty easy to notice. If he moves that ball four an inch to turn it into a strike three, it's a lot more difficult to see.
It's so much more valuable, however. It's why the range of framing runs goes nearly 35 runs from top to bottom, Grandal's +16 to Willson Contreras' minus-18, while the range of blocking is only about 10 runs from top to bottom, and the value of throwing far less than that.
Not every version of Wins Above Replacement includes that value. The one that does has Grandal atop the catcher list, at 5 wins. Second is Realmuto, at 4.3. They're the only ones above 3.5. There's a strong argument that these are the two best catchers in baseball. Grandal's poor October hurts that, but it doesn't undo it.

It's perfectly reasonable to prefer Realmuto's youth, his consistency, that his salary is lower and that he won't cost a Draft pick, and that he didn't just have that high-profile October explosion. That all matters. On the other hand, Grandal won't require parting with Kyle Tucker or Brandon Nimmo or Cody Bellinger -- all names that have come up in Realmuto rumors -- and the real takeaway here is that for teams that are unwilling or unable to satisfy the Marlins, Grandal is more of a 1A than a Plan B. Not every team has those kinds of prospects. They all have dollars.
Okay, so ... who should that be? 
The teams that could desperately use him
Looking at the current free-agent catcher list, the remaining pickings are slim. If you missed out on Kurt Suzuki, Brian McCann, Jeff Mathis, Ramos or others, you're left with Jonathan Lucroy (.253/.319/.348, a mere 77 OPS+, over the last two seasons) or Matt Wieters, who hasn't had a league-average hitting season of at least 300 plate appearances since 2012, or ... well, there is no other "or." You need to trade for Realmuto, or you need to sign Grandal.
You could argue for a lot of teams here, including the Phillies, Astros, Brewers or A's. We'll argue for these three. 
Angels
We say this with tongue firmly in cheek: Name an Angels catcher. Here's the depth chart, but don't cheat. Three of last year's four primary catchers -- Martín Maldonado, Francisco Arcia and René Rivera -- are no longer with the club. None of the three men who caught in 2017 -- Maldonado, Juan Graterol or Carlos Pérez -- are there. Give up?
The two Angels catchers right now are Josè Briceño, who hit .239/.299/.385 as a rookie in 2018, and Kevan Smith, who was claimed off waivers from the White Sox last month. Needless to say, that's not good enough, and it's why the Angels backstops rank as the fifth-weakest in the game, per FanGraphs projections.
The Angels have done a decent job reinforcing their pitching depth this winter, adding Trevor Cahill, Matt Harvey, Dillon Peters and Luis García. There's no better way to continue doing that than by adding an elite framer, one who can help make the inconsistent Angels pitching look better.

Rockies
Much of the same could be said about the Rockies, who currently have the same trio (Chris Iannetta, Tom Murphy and Tony Wolters) who combined to hit all of .207/.314/.354 in 2018. That was part of why the 2018 Rockies had such troubles on offense, and they made their first move to fix that in 2019 by signingDaniel Murphy. 
That's a nice start, but Murphy alone won't fix their issues. If they're really going to start Ryan McMahon at second base and go with Ian Desmond as one of their three outfield starters (along with Charlie Blackmon and David Dahl), then this might be the main spot for Colorado to upgrade. Grandal would be a huge add, not only behind the plate, but next to it, too. 
Red Sox
We understand that there's more to catching than hitting, especially in today's framing-heavy high-velocity game. We also know that the Red Sox won 108 games and a World Series with the catching group they had. And yet, it's our obligation to inform you that 313 hitters took at least 250 plate appearances in 2018, and the bottom three look like this:
311. Chris Davis, Orioles (46 wRC+)

312. Christian Vázquez, Red Sox (42 wRC+)
     
313. Sandy León, Red Sox (33 wRC+)
     That's generally not what you want. It's possible the Red Sox just go roll with this pair (and Blake Swihart again), or that they choose to focus their spending on Craig Kimbrel or someone like him. But there's room for improvement here. Lots of it.