I don't think being the same ratio of bricks to wall as more common cards is necessarily as bad as you think; that ratio gets worse the more wall the card builds; for example:
Palisade wall: 2 wall, 0 Bricks,
Basic wall: 3 wall, 1 Brick (when condition not met!)
Gate: 7 wall, 3 Bricks
Fortified wall: 8 wall, 4 Bricks.
Given the magnitude of its impact, Great Wall of China is actually a much better ratio than the above pattern would suggest.