I certainly agree with the Saurolophine sentiment. (Part of me wants Secernosaurus or Willinakaqe, despite how fragmentary they are, probably that Gondwanan patriotism I suffer from)I would probably want to see Gryposaurus. There aren't enough saurolophine hadrosaurs as it's just Edmontosaurus right now.
Otherwise maybe Shantungosaurus or Telmatosaurus.
And I don't want any dinosaur if it's only gonna be restricted to one person.
We have those... they're called Mamenchisaurus and Dreadnoughtus... the developers unfortunately chose to clone them from the Brachiosaurus...I want the argentinosaurus we need at least one big horizontal sauropod like the apato or the diplo but only bigger