The best home run, of course, is a lefty turning on a righty's grooved fastball, barreling it up, and pulling it to right—not straight down the line, but out toward the gap a bit. Maybe 20 degrees out from the baseline. Obviously we want the exit-velocity slider maxed out here, and give me a launch angle maybe just a few degrees below the supposed ideal of 30: not a straight line drive, but still direct and mean enough that the ball will clearly have hundreds of feet of flight left in it when it reaches the stands some obscene distance from home plate.
A key element here is that the ball must come squarely off the bat's sweet spot, so that it sounds like a cannon blast and everybody in the stadium knows it's gone within a nanosecond of hearing it—so that they watch the ball's flight not to see whether it is a home run, but rather to see whether it will destroy the moon. Also, in this ideal scenario, the hitter plays for the home team, so that the whole ballpark explodes in joy at the moment of contact, and then gets somehow louder when the ball reaches its destination.
That's the most satisfying a dinger can be, something the staff of Defector discussed (argued about) in Slack on Monday because of this tweet, observing correctly that a big homer from a lefty is better than a big homer from a righty.
The Herculean pull-job dinger is also the most thoroughly a single pitch can be defeated: The hitter saw it early, read it perfectly, had no trouble with its movement or location, beat it to the spot, and bashed the ever-loving shit out of it. Visually, on TV, there's the lovely alignment of all the elements heading in the same direction, toward right field: the transit of the swung bat, naturally, and also the ball; and then also the hitter, pitcher, catcher, home-plate umpire, and all the fans seated behind home plate will immediately look that way to follow the ball's flight—and then, because the hitter was a lefty, the body-rotation of the swing opens naturally into a trot in that direction, toward first base, the same direction everybody's looking. It's nice.
All any other type of dinger can do is move some distance away from this ideal. Some deviations don't make much difference at all. Flip the hitter over to the other side of the plate, so that the ball screams into the left-field seats, and it's very nearly just as good, which is to say that it's still great. Pull the ball down the foul line, so that it's obviously gone as hell but there's some brief question of whether it will wrap around the foul pole, and it's fun. (In fact, I don't know why this is true, but this is the one instance in which it's better if the hitter is a righty.) When the ball is hit hard enough to soar high over the top of the foul pole—on the fair side!—it's a nice visual, giving scale to the prodigious dinger. Alternatively, it's generally fine to move the flight path out the other way, fully into the gap, although it won't look quite as impressive on arrival into a lower area of the stadium, and many ballparks don't have seats in that area, so the ball won't drop into a roaring maelstrom of crazed fans.
Likewise, the pitcher's throwing hand makes a minor but real difference. A lefty pulling a lefty's pitch is only minutely inferior, but clearly inferior. A righty pitching to a lefty looks like and suggests one person throwing a baseball at another, the way the righty pitcher's body rotates toward a lefty hitter, whipping the throwing arm in that direction. Also all righties are the natural enemies and hated foes of the noble lefty. All of this gives the interaction an extra zing of juice the lefty-lefty matchup lacks. The same holds true on the other side: Lefty pitching to righty is better than righty-on-righty violence.
Lowering the launch angle a bit, so that the ball laser-beams into the lower-level seats at terrifying speed, is pretty good, so long as it doesn't harm anyone; it's not quite as majestic a visual spectacle but it's still a hell of a thing to see. Sometimes these dingers have a crazy amount of topspin—anecdotally I feel like this is more often the case in the uppercut-swing era—and that's kind of a bummer, because it means the ball looks eager to return to the ground, rather than seeming to have briefly bested gravity. Adjusting the launch angle the other way, so that the ball describes a high, parabolic arc, is a worse deviation. Not only does the dinger lose too much of its terrifying speed on the way up, but it also submits itself too fully to the vicissitudes of the wind, so that when it plunks into the stands it does so at least a little bit shamefully: It got help, or anyway could have.
Only a truly titanic blast, perfect in every other respect, can avoid this penalty altogether: If your dinger is a perfect pull, sounds like Krakatoa, and lands in the upper deck, then the high arc can transform into part of what makes it impressive, like a Paul Bunyan feat. It came down stained with paint it scraped off the International Space Station! It came down in a flurry of white feathers from the angel it de-winged! Shohei Ohtani is good for this type of dinger.
Then there are non-pulled dingers. An opposite-field homer can be cool if it is Vladimir Guerrero Sr. swinging from the heels at a pitch no sane hitter should even have considered offering at—a splitter that would otherwise bounce on the plate, a fastball at eye-level, a slider a foot outside—and possessing the preternatural bat speed, hand-eye coordination, and power to put the sweet spot on that sucker and sock it 10 rows deep the other way.
In basically every other scenario, an oppo boppo feels fluky, looks ugly, and kinda stinks. It's not the loveliest version of the hitter's swing, it doesn't represent the hitter having defeated the pitcher in every way, and anecdotally it doesn't sound as good.
The same goes, to a lesser extent, for dingers to center field. These are better than opposite-field jobs, and can be cool even when done by hitters other than the elder Vlad Guerrero! But in general a swing that socks the ball into center has a sort of ungainly finish, and the overall affair just isn't as spectacular an act of violence. Plus it always feels like a waste when a properly smashed baseball ends up plopping into the batter's eye backdrop in center. You have to hit a center-field homer 500 feet for the ending to look particularly exciting.
Distance in all cases is a factor. Except in the very most thrilling and fraught of circumstances—bottom of the ninth, two outs, a runner on, a one-run deficit, Game 7 of the World Series, a Houston Astro pitching—it frankly stinks when a homer just barely makes it over the wall. For a fan without a clear rooting interest in the outcome of the game, you'd always rather see the great dinger-robbing catch, both because it's rarer and more dramatic than a dinger and because a dinger that barely clears the wall—a dinger that can be caught—has no right to be a dinger at all. It's a fraudulent dinger!
In fact, here I will go so far as to say that a hard line-drive double, drilled deep into the gap or ripped down the line into the corner, is generally better than a pathetic little baby dinger hit short enough for the outfielder to attempt a catch. It can be a masterwork of hitting, for one thing, and then it also involves fielding and running and the possibility of being thrown out, so it's a more complete baseball event.
Likewise, do not waste my time with dingers hit off the end of the bat, or fought off the knuckles, or in any other way not caught squarely on the sweet spot. Do not bring to me a dinger that sounds like somebody snapping a number-two pencil. Nothing in sports is more disgusting or contemptible than when a hitter swings under a pitch, hits it more-or-less straight up into the air, and gets rewarded with a free jog around the bases for it. I have no appetite for these dingers, for they do not represent good hitting at all. One hundred times out of 100 I will take the hard-hit double into the gap over the shameful end-of-the-bat homer. Hell, for that matter, give me a slick professional single, smoothly and intentionally placed in front of an outfielder, over some poorly hit piece of trash that clears the wall purely by dint of wind and weightlifting.
The worst type of home run is when the Boston Red Sox hit one.