My favorite Rhino villager is Spike. I had him in my town back on the GameCube. It's nice to see that he returned in the Welcome Amiibo update, and I might be interested in reacquiring him in the next game if we're allowed more than 10 villagers. I like the little added character from his scar, his Cranky personality, his orange coloration, and the blue and yellow accents on his hands, feet, horns, ears, and tail.
Hornsby is my favorite rhino, by far. I had him in the GameCube game a long time ago, and his memorable catchphrase of "shnozzle" always stuck with me. I've since used an Amiibo card to add him to my New Leaf town.
Not the biggest fan of Rhino's, but I do quite like merengue and hornsby, shame it's basically impossible to get WA cards now because otherwise i'd have him in my town
I say Hornsby is the best then the other rhinos because his design is pretty nice and not ugly and he is pretty normal looking and he is lazy.
I'm no fan of the other rhinos, the other rhino villagers are pretty ugly.