by grarrrg
Most of what you just said has been explained (officially, but not entirely) in other threads.Kraken>Space Penguin: since they had to replace Bunny, and they wanted to do Cthulhu at some point, they decided Kraken was a bit of an overlap, so they decided to swap penguin in, as it had previously only been available as a promo.
There is one point of contention on your Bunny name explanation though. They are allowed to reprint the Power Up cards that say Cyber Bunny (no art). Whether this is a special exemption from the legal case, or what, we don't know.