>>33878591A matter of hidden depths.
In Maxie and Archie's case is to show that they are just dumb fucks with good intentions, no plain evil. Cyrus is a bit tricky but my guess is either emphasis on his charisma or he isn't as cold as he thinks he is. Giovanni owns a Crobat only in the manga iirc but still counts, since it seems he likes his own pokémon even if he makes a business out of stealing others'.
Silver had to wait because he was getting character development, the villains are already grown up so they don't need to do the same rival's journey.
