Poach analysis:
Chocobo: Nothing even remotely broken here.
Goblins: Easy way to get Assassin Daggers at start of C3. It's a 3 WP jump from Platina, and only a 1 WP jump from the storebought dagger after the Orbonne sequence, plus daggers aren't exactly broken weapons.
Bombs: Scorpion Tails are abusable. But they only come off Explosives, and only a few classes use flails (the only really offensive one is Ninja). You can get a totally absurd Ninja if you go and poach two of these, yes, but it's not THAT bad, also considering how many nerfs they got in other areas.
Panthers: FS Bag is gimmick, not broken.
Squids: Books are woefully underused. I have no issue with getting one a chapter early. Dracula Mantles are very nice, but a defensive accessory rather than an offensive one, which generally get less mileage, plus they're on the third tier monster.
Skeletons: Have yet to see anyone even use the improved Cursed Ring! Ivory Rod is cool but hardly broken.
Ghosts: Early Ice Brands are nice, but you could get them in normal FFT too and they're actually nerfed (1 less WP). Vanish Mantles are only abusable if doing a full-party strategy, and Muramasas can do the same thing.
Flotiballs: Early Reflect Mails are double-edged. They certainly make heavy armor classes more viable from the raw HP gain, but you've got to deal with the reflect, too, and heavy armor could use the help honestly. Zorlin Shapes are overpowered this early, but Plagues are not overly common (Scorpion Tails still beat them for potential broken on Ninjas, and I'm not worried about Thieves being too good).
Birds: Yep, you can get a super easy Gastrafitis. Yes, this doesn't bother me, because crossbows don't get used enough and there aren't even any rare crossbows. Ultimus and Yoichi are slick and encourage using lategame Archer, which again does not bother me (getting people to break out of old FFT stigmas).
Pigs: Still absurdly rare till C4, so not really a factor. Chantage doesn't come off them anymore either.
Trees: Only the Whale Whisker is notable; the other two weapons are kinda niche. Does make stick beetz Oracle great for a while, but that's one class that requires them to get into near melee range.
Minotaurs: Katanas are still kinda crappy weapons even if you're getting the endgame WP. Kikuichimojis break, so you have to stock these up to make the ability viable early on (and was the most nerfed Draw Out by far). Holy Lances were always common poaches. Mace of Zeus is more awesome than broken.
Morbols: See Squids about books, plus they're considerably rarer than squids.
Behemoths: C4 monster
Dragons: Defender being available is GOOD as it means Knight Swords actually exist before C4 (there's also one stealable at the end of C3 added by LFT). Dragon Rods are a shiny Wizard Rod, also a C3 weapon. Dragon Whiskers make Lancers broken for this stretch, but Red Dragons are not the most common sight ever and you could, again, pull off the same in vanilla FFT.
Hydras: C4 monster