Well rares nowadays are like very OP and my card is 6 mana for a combine of a 6/6 which is just right. And the only special thing added was flying and lifelink so I still think it should be uncommon.
For the bat token thing maybe I should do this:
When Vampire Bat-Keeper enters the battlefield, put 3 1/1 black Bat creature tokens with flying onto the battlefield.
Bat creatures you control have flying.
Well anyways nice contest!