Beat me to the punch.
Well, in any case, here's my list of sauropods I think could - and should - be added to the game. Whether or not they are depends on Frontier and Universal's plans for the future, but I think these would all make for interesting additions to the game:
10)
Lessemsaurus: At an estimated 30ft (9.1m) long, this Late Triassic sauropod would make an excellent addition to a Triassic Pack, should one be ever developed, and never hurts to add more "mid-sized" sauropods to the game. At present, it's only known from a few vertebrae, but a lack of complete fossil material hasn't stopped the devs
before,
right?
9)
Rhoetosaurus : Another sauropod known from only a few remains, it's also one of a few species found in Australia, and we can always use more dinosaurs from "The Land Down Under." At about 17m (55ft) long and 4m (13ft) at the hip, it would probably be a mid-range sauropod in the game; larger than
Apatosaurus and
Diplodocus, but smaller than even
Camarasaurus.
8)
Amargasaurus: Why this "spiky boi" hasn't been even considered by the devs, I will never know. But this 10m (33ft) sauropod would be a welcome addition to the list of South American fauna to the game, which we all known could use a boost.
7)
Saltasaurus: On half of the reason I felt the
Ankylodocus hybrid in the game was redundant. At 8.5-12.8m (28-42ft) in length, it'd be comparatively smaller than the in-game sauropods, even
Apatosaurus, but the osteoderms along
Saltasaurus' back would make a unique looking addition, especially alongside the aforementioned
Amargasaurus. Plus its smaller size could mean a lower price and quicker incubation for players.
6)
Shunosaurus: The other reason I felt the addition of
Ankylodocus was redundant. At 11.5m (36ft) in length, this club tailed sauropod wouldn't be as large as even the smallest of the current collection of in-game sauropods, but a smaller size could mean lower cost and less time for incubation, which could be attractive to players, while the club would make it unique among the regular sauropods.
5)
Cetiosaurus: Arguably the first sauropod discovered by science and the most complete one found in the UK, and we could always use a few more European dinosaurs. This sauropod would have grown to about 16m (52ft) long and could be added to "English" exhibits alongside
Baryonyx,
Polacanthus,
Metriacanthosaurus and
Iguanodon.
4)
Nigersaurus: As
Pixelated Sparkster pointed out, at 9m (30ft) long, this African sauropod wouldn't be considered one of the largest, but with a head shaped like a vacuum hose attachment, it would certainly be one of the more unique in appearance. And we could use more African herbivores than just
Kentrosaurus.
3)
Europasaurus: If some of the sauropods I've already mentioned seem a bit on the "small size," at least by sauropod standards, then this sauropod would be considered absolutely puny! With adults estimated to have grown up to 6.2m (20ft) long and weighing around only 907kg (2000lb),
Europasaurus's small size is believed to be a result of the island(s) it lived on at the time, as mainland Europe (including Germany, where it was found) was little more than an archipelago during the period it lived. If you ever wanted a sauropod that would be perfect for a petting zoo, this would be one of them.
2)
Magyarosaurus: Another sauropod that would be perfect for adding to a petting zoo; you just have to make sure they were bred not to bite! About the same size as the aforementioned
Europasaurus (6m (20ft) long and around 1.1metric tons (1.2 short tons)), this sauropod from Late Cretaceous Romania would be considered puny by sauropod standards, but an attractive purchase for players on a budget, depending how much time and cost Frontier decided this animal would take.
1)
Brontosaurus: 2015 brought
Brontosaurus back out from under the shadow of
Apatosaurus, and it could be time for the original "thunder lizard" to shine again. At 22m (72ft) long, it would be around the same size as the in-game
Apatosaurus (maybe a little smaller), and the name alone could give the animal a boost in its base ratings. It's similarities with
Apatosaurus, however (a major reason it was classified as a the latter for over a century) might make this sauropod the one most unlikely to be implemented. Although, if Frontier can make
Deinonychus look different from
Velociraptor (considering the latter is basically the former IRL), they could probably do something similar between
Apatosaurus and
Brontosaurus.