@Tomatosoup:
Going through some ones that seem not so wonderful at first glance (not that I don't think they're wonderful though). Buggy, Blamenco, Miss Valentine, Bellamy, Kalifa, Very Good, Sharinguru, Tsuru, Pierre, Apis (anime filler).
Buggy is already using his Fruit at a moderately strong level, he just has the misfortune of having a really weak body. He seems to make up for this by hiding weapons between his bodyparts (only explanation I can think of for the Muggy Balls), which is a clever use of his power. Really what he should do is wear more weapons on his limbs, like heavy iron gauntlets and bracers and such. Being hit by a dude's forearm isn't that painful, but when it's encased in metal and rimmed with spikes, it can mess you up.
Blamenco's Fruit is significantly more useful than just holding stuff. Well, I mean, all it does is hold stuff but… let me explain. First, he gets to defy physics. His pockets are bigger on the inside than the outside. That means he can, presumably, hold ANYTHING in his pockets. Cannons, giant weapons, ships, boulders, lances, explosives... I can think of a dozen uses for a 'bag of holding' off the top of my head. There's presumably no problem with him using it defensively either. You shoot at him? He puts the bullet in his pocket. You slash a sword? He aims the tip in his pocket.
Miss Valentine's power should be godly, if she's able to control the weight of a specific part of her body. Force is equal to mass times acceleration. And she's able to alter her mass in an instant. Every kick, punch, slap and poke should be capable of crushing stone through selective alteration of weight at the right moment. If all she can do is alter her whole body's weight, then, unfortunately, the only other way for her to get better use of her Fruit, is to use weapons. A spear would be fantastic in the hands of someone who can leap several stories into the air and then crash down on a target, and she'd make a very impressive sniper, with her quick movements and sudden eagle-eye vision.
Kalifa and Tsuru's Fruits are similar so I'll just say... Debuffs are fantastic. Kalifa's Fruit let her move from being useless against Sanji, to utterly trouncing him. Now, he wasn't able to strike her, but she clearly was at a disadvantage before she started using her powers. Of course, then she went entirely in the other direction and basically only used them against Nami. But yeah, being able to defeat an opponent who might be more powerful than you, by 'cleaning the strength away' from them is awesome. Kalifa could have beaten Oars on her own, for example. Unless you know the secret to beating her effect and can take advantage of it, Kalifa's power is awesome. Tsuru's too, by extension, but I only know that one vaguely.
Very Good's powers though... come across as a less useful Buggy. Now, he himself seems to be a better fighter, to the point that the Marines sent him after CP9 to arrest them, presumably believing he stood a chance to do so. If I remember correctly, he's immune to blunt attacks, and can float around as orbs.
Sharingu has the same solution as Miss Valentine. Hold a weapon and let your increased speed hit the enemy harder than normal. Since the speed seems to be mechanically driven, he should use a really heavy weapon, like a giant hammer, or a weighted chain weapon.
Pierre's power is only useless because he's a bird. Zoans in general are more obvious in application than Paramecia. Really, there's not much I can say for a riding-bird that turns into a horse. If anything, it seems like a downgrade... maybe Pierre has more endurance because of his Fruit? I dunno.
Oh, and Apis' power IS useless. It was made by the anime, replicated by Luffy just being Luffy, joshed later in the series as nothing interesting or super-special and doesn't imply any level of control over the animal you're speaking to. Plus Chopper, Bepo and Pappug can do it, just because they are bilingual. So yeah. Poorly made powers that aren't thought out well, aren't that great.
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