I would really love a Therizinosaurus in JW3. It would also be a great dino to introducing feathers into the series. Here is a version I kinda photoshopped to show what it would look like.
Edit: I'd also like Iguanodon to be in JW3 and the JP Dilophosaurus and the original Mattel toy of the Pachyrhinosaurus to be in it as well. The rest can be dinos from Fallen Kingdom.