A hypothetical aviary expansion is it?
Hmm... let me think...
Pteranodon would be an obvious addition... for obvious reasons.
Dimorphodon... well it does appear in the movies... but is it big enough?
Quetzalcoatlus would be awesome... carnivorous giraffe with wings...
Tapejara would be nice... that big crest could be very pretty to look at.
Rhamphorynchus is a classic pterosaur... although it suffers the same problems as Dimorphodon; it's kinda small...
Djungaripterus and its crazy beak and blunt, crushing teeth would be a nice addition.
Pterodaustro has that crazy under-bite; large teeth meant for filter feeding... it too joins Dimorphodon in the small size department...
Nyctosaurus has that bizarre antler crest... also small like Dimorphodon...
There's actually plenty more to suggest... but I think I'll stop before it gets out of hand.
Also, I notices a few people suggested Ornithocheirus... but is that because of how it was depicted in Walking with Dinosaurs? Because the massive wingspan attributed to it was purely fabrication and what materiel is known suggests an animal closer to Tupandactylus in size; a five-ish meter wingspan... smaller than a male Pteranodon.
Personally, I just like Ornithocheirus. The small crest on the beak in particular makes it unique. I first saw it on Prehistoric Planet, which I believe used the Walking with Dinosaurs clips.