Hey there! 
i actually dont get the point of silver or higher cards. Its kinda pointless to go, e.g., for a gold Nader if u got a decent bronze Naderwith nice abilities. Ive got a gold Nader already, but dont use her cause my bronze one is better then the gold one.
Thats killing the fun abit tbh, cause i rly enjoy the way u can get rare cards.
So in my opinion the abilities should get increased slowly with the rarity. For example: one of the Nader abilities is, that the range of the grenades increased by 10% (bronze). So it would be nice if a Nader silver card would give 12% or 11%, or just any range increasement. Just to make sure that theres a difference to a bronze card.
More over a gold card should be better than a silver card and so on.
What you think?
Greetz Tupper
