Looks pretty good to me. I don't think that the rules are that complicated, but they could definitely be written in a more simple way.
One question. Is there are reason you have "cells"? To me all that talk about cells make it very complex because it's a new concept. Why not just talk about cards?
If you say "your deck must contain 6 different cells", isn't that's basically the same as saying "your deck must use exactly 6 different types of cards"?
And instead of saying "increase or decrease the size of any cell by 1", you could simply say "take a new copy of a card you already have in your deck".