It's as if people just want to be handed collectible items or something. The game has plenty of things that can be specifically targeted/grinded for, and additionally plenty of things that are luck-based. Both of these usually also require some dedication or perseverance, and while RNG can be frustrating at times, some grinds can be frustrating as well even when you know exactly where the goalposts are, such as the Argent Tournament, Ravenholdt's junkbox collecting (and turning them in), and Talon's Vengeance rep as well.
To get back on-topic, I'd expect most if not all mounts from paragon rewards (if any) to be recolors, with maybe one being something more distinct/unique. That was the case in Legion, with the storm drake from Valarjar being the one 'exception' I'm thinking of (even though that was essentially just a recolored drake as well). Horses for the Alliance, dinosaurs for the Horde, and a probably aquatic/sea turtle mount from Tortollans. I can't really think of one that I'd personally be satisfied with for Champions, though. Maybe a ram made of diamond, like Magni? Blizzard could even write in its description that it's Magni's actual mount, with some handwaving explaining how it somehow turned to diamond like its master.
Pets and toys are definitely possible as well and would probably be the reward from several of the factions. Most things that are suitable as mounts could also be downscaled to pet-size, with a few more possibilities as well. A wicker construct for instance from Order of Embers; perhaps a siren from Proudmoore Admiralty? Toys could be just about anything, and I can't really think of anything myself as to what those might do.