Yeah, introducing new characters. Totally big reason to quit. NOBODY is going to quit over Para and Dox being characters. Why would they? There is no downside to them being in this game. (Oh no, you'll have to wait longer for x random character you want!11) It's not like they decided "Hey, Marik has too much hair, let's replace him with Para and Dox."
Sangan, suijin, kazejin when first came out were suppposed to be "god" like cards and gate guardian an unbeatable monster. They failed. Almost 20 years and Konami has totally forgotten them. I would like to see some serious support for these classic cards...