Freedom cards give you double the attribute bonus of the gate card.
Thats all? I could easily use a Shadow card to take away your bonus. Or I could do the same thing as the Freedom Card by using the ability card Rock On. It doubles your attribute bonus, and your ability cards. Now thats more powerful.
The Shadow cards won't work against the Freedom cards since, the Freedom cards can only be played on your opponents Gate card and you can't play a Shadow card on your own Gate card. The Rock On Ability card only works for Haos and Sub Terra types, so these Freedom cards are almost the same but for the other types as well.