As anyone addicted to cubimal buying knows, you get a lot of spares. While releasing them is fine, I'd rather keep them and combine them to form a super cubimal.
Either combine 11 of one kind to form a bigger cubimal (e.g. 11 sloths transform into 1 super sloth or- for insane people- 11 rubes transform into 1 super rube )
or
combine 11 arbitrary cubimals (say 5 sloths, 3 foxes, 1 butterfly, 2 piggies) into 1 Frankenstein's monster-style cubimal that is customizable much like the butler.