These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Dark Cloud
Character Tiers: Overall, Toan and Xiao are the best, because they're easy to be effective with. Goro and Ruby are harder to use, but can be argued to be the best when used properly. Ungaga and Osmond are the worst, partially because they join so late in the game, but still have their uses. To the game's credit, all the characters can be made into complete killing machines through the upgrade system and they're all not useless even without that.
Goro's weapons often have a high attack power and durability. His charge attack can deal insane amounts of damage when executed correctly, and is essentially an even stronger version of Toan's second charge attack, meaning he is invincible while executing it. However, his basic attack has a very poor hitbox, and comes out slowly, meaning he can be difficult to use without careful planning. Furthermore, unless he's using a weapon with a high speed, he will sometimes be completely unable to attack for a few moments, which is a huge issue. That said, he boasts the highest single-hit damage in the game, making him excellent in specific situations. He also runs slightly faster than Toan, which combines with his high power in a way that makes him a nightmare for enemies who try to stay at a distance. His Battle-Axe weapon, gained from completing all the requests in Matataki Village, is excellent overall, and will likely be the first weapon player gains with a high-enough speed stat to avoid his biggest problem.
Ungaga has three things going for him: his excellent reach/hitboxes, his damage-per-hit not lagging far behind Goro, and his charge-attack, which racks up damage quickly. His weaknesses include his weapons being very fragile, and his attacks being somewhat slow. The problem is that his excellent reach oftens means hitting multiple foes, and multiples hits against guarding foes, which synergize with the aforementioned fragility to mean that his weapons can break in just a few poorly-timed attacks. Further, his reach means little in a game where half the cast has projectile weapons. Luckily, the Mirage that the player is given for completing all of the requests in Muska Racka is an excellent weapon, and as long as the player is careful with his attacks, he can actually be rather useful.
Ruby's weapons are largely based on their Magic attribute, and as such the player often has to manage her active elements to exploit enemy weaknesses if they want to get good mileage out of her, which is fine, but slows the game down. That said, she's the only ranged attacker with a charge-attack, and a close-range charge-attack that strikes the enemy's weakness can do more than respectible damage. Unfortunately, being close-range negates the point of using projectiles, and, while all ranged character's damage drops off as distance is added, Ruby is affected the most by this. Further, of the long-range characters, Ruby has to stop moving the most when attacking because her animations take longer, which means making herself unnecessarily vulnerable, especially when combined with her need to get close to deal her best damage. Ruby also has the interesting property of 'half-charged-attacks', wherein she begins charging an attack, but fires before completing the charge, which deals markedly more damage than standard attack, without the extra damage to your weapon of a 'proper' charged attack, which means she can be the most efficient damage-dealer in the game. Unfortunately, this technique means she has to stand still even longer, exacerbating her main weakness. She and Xiao gain weapons with the 'steal' trait, which sometimes gives the player items when they hit enemies, and does not affect the enemy's likelihood to drop an item on defeat. This makes them both very easy on the player's wallet, and means Ruby is an efficient attacker in two ways.
Xiao gets a lot of flack for having a weak starting weapon, but this can be remedied through grinding, and proper use of a few synthspheres. Once this is out of the way, Xiao becomes arguably the best character in the game, with early access to crazy-high attack, a higher firing rate than Ruby (and Osmond's non machine-gun weapons), very little delay when attacking, and the highest movement speed in the game, which all combine in a way that makes her an insane DP Ser who has no trouble dodging anything at all. She also has sole access to Steve and Super Steve, a pair of unique weapons that advise the player on how to deal with enemies it targets.
Osmond is a promising character who's added to the party too late to really shine. As a result of when he appears, he has the smallest selection of weapons in the game, and is somewhat less likely to end up with maxed out health or thirst than anyone else (as the player has likely used the limited supply of items that do this on their other characters). However, he's the only character in the game who doesn't have to stop moving at all when attacking, and his machine gun weapons can rack up damage very quickly when buffed the right way. Unfortunately, his machine guns have very poor damage-per-hit, and compensate by attacking extremely rapidly, as is appropriate for a machine gun, but that means that his weapons break far faster than any other ranged character (and even melee characters, provided that they are not hitting stone/metal monsters). His other line of weapons is a series of elemental flamethrowers, which are very strong overall, but have a limited range, which forces Osmond to forgo the "long-ranged" part of being a long-ranged attacker, which exposes him to extra damage, which combines with his likely-not-maxed-out HP in a way that brings him down.
Fan Dumb: When the game was being advertised, PS2 fans took the "Zelda Killer" angle and milked it for all it was worth in several take thats directed at the Nintendo's rival series, The Legend of Zelda. They ate crow when Dark Cloud only did mildly well and Zelda retained its crown.
Goddamned Bats: The dragon enemies that shoot fireballs from a distance, and tackle you when close, causing Stop status.
Game Breaker: Synthspheres. Characters in this game are about as strong as their weapons, and Synthsphere's are weapons turned into weapon-attachments. Equipping just about any one to a given weapon will max out at least 2 stats. Consider that you can make synthspheres from the weapons of your strongest characters, and attach them to the weapons of your weakest, and it becomes an easy way to subvert Can't Catch Up.
Jerkass Woobie: Goro. Mouths off and acts selfish during his only speaking roles, but suffers deeply from father issues and abandonment issues.
"Pumpkin Panty Fortune Telling". There are no words to describe it. Monica's default costume has a piece called Pumpkin Shorts. Is she related to Yaya?
They actually drew Dran's butthole and the game has graphic deaths scene when fighting the Killer Snake. Both yours and the snake's.
That One Boss: La Saia, who has a bunch of ice attacks that can hit you from pretty much anywhere. One in particular freezes you, regardless of whether you have an anti-freeze amulet equipped, and lets her get 1-2 powerful shots in.
That One Sidequest: Use "Items Only" to defeat enemies. Especially when the level is populated with high-flying Goddamn Bats, and items are expensive.
Tier-Induced Scrappy: Goro and/or Xiao. They both benefit drastically when upgraded properly, which means they start very weak, and seemingly useless, causing most players to try them out, and then write them off with no second thoughts. Played with, in that the game's upgrade system can turn any character into a total Bad Ass. Ungaga and Osmond are the real worst characters overall, but avoid this due to being cool as hell.
What Could Have Been: A speculative example. The Duels in this game are battles played out through Quicktime Events. There are very few of them, and the final one is a big anticlimax, it's not even a fight, and it happens about 70% into the game (the third-to-last dungeon starts collapsing, and you have to Duel to cross a bridge). Some players speculate that the Dark Genie vs Sun Giant fight was supposed to be a Duel, as it plays out like one visually, and would have an appropriately climactic use of the mechanic.