Just thought I'd summarise and add a couple of the stranger suggestions I've thought up as a sort of Dino pack (though it can't really have an opposite, considering the nature of the game licence).
Inaccurate dinosaur pack
Notoceratops - Late Cretaceous, Argentina - Lago Colhué Huapí Fm. (most likely, but could be other Chubut group members)
-Arboreal Ceratopsian-
Mainly inspired by the Microceratops from the Jurassic Park novel, it also seems like the only type of potential for a member of the Ceratopsid paleobotany group to use the Tall herbivore feeder.
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Notoceratops as a candidate is only known from a single, toothless jaw, that we now only have drawings of (so alot of freedom with design) and might not be a ceratopsian at all.
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Morphology wise, something akin to Leptoceratops (that's more quadruped) as a base would likely be best, with the main different feature being opposing digits, either one like a monkey/possum, or two like a koala/chameleon. Also, in a general sense, the forelimbs of climbers tend to curve forward (particularly the ulna in mammals, though for a ceratopsian the ulna is quite short, so it might be more so the humerus for this).
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In terms of things it could climb, there's the Tall feeder and potentially reusing the code for interaction, I could imagine a future placeable tree or two being suitable for resting.
Qantassaurus - Early Cretaceous, Australia - Wonthaggi Fm. (aka Flat Rocks)
-Hopping Ornithopod-
Hopping dinosaurs is generally a pretty old, outdated idea (originally for theropods), though the idea of the Othnielia from the Jurassic Park novel is something I'm quite the fan of. Having them hop like a kangaroo and be arboreal though is probably a bit much given the game context and amount of effort.
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Qantassaurus as a candidate has limited material (being known only from jaws and teeth), leaving freedom with design and is named after a company who has a kangaroo as it's logo.
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Proportion wise, I'd say leg proportions should change, with Kangaroos having a longer shin in particular, though accurate proportions for the type of dinosaur could work too. Having a bulkier tail might also help with balance appearance. One other thing to remember is the padding for the foot extending up to the ankle, particularly if it rests on them.
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Also pentapodal movement would be difficult/impossible for such short limbed animals, so being able to walk moving their legs independantly is logical, such as with Tree Kangaroos and the extinct Sthenurine kangaroos, though it's your choice as to whether or not it walks on it's ankles.
Brachypodosaurus - Late Cretaceous, India - Lameta Fm.
-Fishing Ankylosaurian-
The idea of a fish eater Ankylosaur isn't new, Liaoningosaurus has been found with fish in it's stomach area (though there are explanations other than being a piscivore, such as movemont of bones after death), however it is probably too small to be a realistic candidate (about 34cm long as a possible adult) and really needs proper swimming animations both in and outside of the fish feeder.
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Brachypodosaurus as a candidate leaves a lot of freedom with design (known from a single foot-long leg bone, whole animal estimated at 4m I think) and it may actually be a Plesiosaur, so a partial diet of Fish would be fitting if that's the case. Even if it is actually a dinosaur, the diet might not be too far-fetched, given it's island habitat of India. The name is also safe as a dinosaur in Indian textbooks, due to being the first ever dinosaur described by a local, Indian patriotism should not to be underestimated.
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Design wise, there are multiple avenues you could take to make it adapted to a "fishing from the shore" type of lifestyle, suitable to use of the fish feeder.
My personal preference involves it's tail having a long, rigid part on the end, suitable for whacking and stunning fish when submerged (like the bill of a swordfish), with the animal then collecting prey with it's mouth, though alternatively you could go for a more passive style of fishing, having a worm-like end to the tail to use as bait (like the tail of a death adder).
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I was thinking that a slightly longer skull would also make sense, though keeping the triangular profile from the top. The beak could be strongly serrated and maybe slightly hooked to fall in line with the style of crocodile/Spinosaurid/plesiosaur teeth, or at the very least hooked at the end like an eagle.
Hooked claws on the front limbs is also something that could be done, though I'd figure it's best to limit the Spinosaurid commonalities when possible.
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You could have the Fishing Ankylosaur of choice be either omnivorous or purely a fish eater. From a defensive perspective you could make it defenceless, or give it minimal defences attacking in the same manner as the Nodosaurs. If going for the sword-tail design you could also potentially have a finisher that involves being pierced by it (with kills of people by swordfish being accidental, I don't really see it being useful defensively, but if it didn't use it that way, people would complain about wasted potential).
Honourable mention
Rapator - Late Cretaceous, Australia - Griman Creek Fm. (aka Lightning Ridge)
-Alvarezsauriform Megaraptorid-
Based on the fact that it was once classed as a giant Alvarezsaur, I was thinking a sort of inbetween design would be interesting, being known only from it's large claw there's a fair bit of freedom. Also being a carnivore it gets around the need for insects of actual Alvarezsaurs.
I'm pretty sure most aren't particularly into this sort of thing (ranging from historical inaccuracy to straight up making stuff up) and that's completely understandable.
