Mob vote

I have an ideal for the mob vote system that I think people will really enjoy, in the mob vote Everytime you release a new 3 instead of creating and coding 3 new mobs why not put in 1 only 1 old mob from past mob votes so it gives people the chance to have both for example the newest one people are going to want both the crab and the penguin so next mob vote bring back one or the other instead of coding three new mobs, should it not be faster easier and cheaper?