I've wanted to build a vintage Bentley (circa 1920's) for a couple months now, so I did. And I was in mood to build a dinosaur, so I did. And I put them together... in retrospect, I don't know why they go together, they really don't, but what the heck, right? I think of this pairing as my own little Dino Island playset. The dinosaur was inspired by the Styracosaurus, but it is my own original design/horn configuration, that would have been found in the family Ceratopsidae, along with the Styracosaurus and Triceratops. He's a little more slender than his would-be family members.
Wonderfully imaginative as usual, Jordan! Grouping them together isn't a problem (unless you're a Valet Parking Attendant!)...like you said, your own little "Theme" set. The Ceratop is superb...but that Bentley may be one of the best 6 wide Automobile MOCs ever...splendid!