I have a feeling that 2.6 will add creatues which families are apparently missing an epic, rare and common creature as well as uniques and legendaries. This list has candidates for hybrids and new creatures
Uniqe hybrid candidates : Eremoceros, edaphocevia, phorusaura, alloraptor
Legendary hybrid candidates :
Megistotherium, troodon, ovilophosaurus, Scutosaurus
Epic candidates :
Citipati, Megatherium, Panochtus, Daeodon, gastornis, dinogorgon, Prestosuchus, Archaeornithomimus
Rare candidates :
Deinotherium, gigantophis, Polacanthus, archilobator, glythornax, Archaeocypion
Common candidates :
Anzu, Thylacosmilus, Synthetoceras, Mastodon, megalochelys, Pareiasaurus
Edit : since ceratosaurus was featured in camp cretaceous s2 i say he has a 75% chance of getting added unless he becomes a event exclusive li