I think there are many leaders in the game that look far worse and have far worse animations--Pedro II looks nothing like he did in real life and instead looks like an Aardman animation character; Tomyris and Hardrada have weirdly jerky animations, Gandhi looks like Gollum, etc. At least Barbarossa looks (in his face) like certain paintings of him, and the long beard of Barbarossa you speak of shows up in few works portraying Barbarossa in his older days, and certainly his beard is at least full enough to lend credence to the idea that people gave him a nickname based on his beard.
Pericles in my opinion is one of the most ahistorical portrayals in the game along with Pedro. He may lack the jerky animations of Tomyris, but he's definitely weird and completely ahistorical. Not only is the helmet not a fit (let alone practical), he looks like a weak old crazy doomsayer or cranky librarian with a Zeus beard (or a comic portrayal of Archimedes) instead of the real Pericles, a more majestic and healthy (and youthful) looking general with a less unruly beard and a more practical and realistic helmet.
Also, no, many people literally *just* took issue with Barbarossa's armor. See the Facebook discussions of the Barbarossa first look videos for one, and these forums for another. You are the first person to criticize his facial appearance that I have seen.