There are some clear stand-outs, some clear losers, and a vast middle ground.
It will not surprise anybody for me to rate Fenway Park at the top. I admit my Red Sox bias, but I think the quirkiness of the ballpark, its history, and the way it is just infused with baseball atmosphere are valid criteria for its placement. And everybody sings along!
I debated between whether Camden Yards (Baltimore) or Whatever Phone Company It is Named After Today Park (San Francisco) is next. I decided San Francisco has a slight edge since: a) it has better transit access, b) it has better beer, and c) they don't play "Take Me Out to the Ball Game" in Baltimore. (They play "Thank G-d I'm a Country Boy." This is just wrong.)
I wanted to like Wrigley Field (Chicago Cubs) better, but I had a seat with so-so sight lines, the sound system sucks, and I hate that the fans throw back home run balls hit by the opposing team. I do like its quirkiness and history and fan energy. And they score high on singing along.
The next group includes PNC Park (Pittsburgh), Coors Field (Denver), Comerica Park (Detroit), Citfield (NY Mets), Nationals Park (Washington), Turner Field (Atlanta), and Progressive Field (which was Jacob Fields when I went to a game in Cleveland). They're all very nice places to watch a game, with enthusiastic fans, reasonable access, and at least some local character, without anything notably annoying. I hesitated most over Coors Field, due to mascot annoyingness, but they got a boost by being the one ballpark that actually tries to enforce people not moving in and out of their seats during play.
Since I live in this region, I should note that Nationals Park got credit partly for not being RFK (a truly awful place to watch a game) and partly for having particularly good local character in the concessions (Ben's Chili Bowl! Gifford's Ice Cream!). It would move up a notch if the fans were more engaged. Washingtonians have been seen singing along. They sang to Gershwin at a show Robert and I saw at Ford's Theatre. They sing along at Wolf Trap. So why can't they sing along to "Take Me Out to the Ball Game" like all loyal and patriotic Americans should? I could also do without the presidents' race nonsense.
Yankee Stadium (aka the Heart of Darkness, as the Source of All Evil in the Universe is the home team) would rate in the previous group if the ticket prices were a lot lower. They've priced the average fan out. And nobody sings along.
There's a vast middle group of bland ballparks. They are perfectly pleasant places to watch a game, but lack local character or fan enthusiasm. Or they annoyed me by having multiple mascots (Cincinnati), unrecognizable alien mascots (Philadelphia), more than one ceremonial first pitch (Saint Louis), etc. I am also biased against teams named after states instead of cities, which may have influenced my ratings. That group consists of Chase Field (Arizona Diamondbacks), Great American Ballpark (Cincinnati), Minute Maid Park (Houston), Miller Park (Milwaukee), Citizen's Bank Ballpark (Philadelphia), Busch Stadium (Saint Louis), Petco Park (San Diego), Edison Field (Anaheim, not Los Angeles), U.S. Cellular Field (Chicago White Sox), Kauffman Stadium (Kansas City), Target Field (Minnesota Twins), Safeco Field (Seattle), Ameriquest Field (Texas Rangers), Sky Dome (Toronto). Again, there is nothing actually wrong with any of these ballparks. They just lack soul.
Dodger Stadium (Los Angeles) just misses out on that group because of how many hours of my life I've wasted searching for my car in its parking lots after games.
Finally, there are the awful places that need replacement. Dolphin Stadium (Florida Marlins) and Network Associates Coliseum (Oakland A's) are the last of the multi-use stadiums that were so popular in my childhood. We also thought TV dinners were a good idea back then.
Rock bottom is Tropicana Field (Tampa Bay). If I were given the ability to wipe one building off the planet, this would be my first choice, followed by the Iranian nuclear reactor and the apartment complex I once lived in in Berkeley where none of the walls met at right angles. Indoor ballparks are an abomination and there is a reason this is the last permanently domed stadium left. I may also have been biased by the horrific traffic to get there, with particularly surly traffic cops directing things. But there is no excuse for the clanging of cowbells. Learn to cheer like normal people and then we'll talk.