Peakmonsters says that you've got well less than $600 worth of cards (many of which you've probably gotten from the currently excessive rewards)
I've got enough maxedout and high level cards that I've spent ~$500 usd buying and I do beat on regular other players with maxedout cards.
Your collection rating says that you've got well less than $500 of non-duplicate cards.
Which only proves that investing $500 usd in this game is not a smart idea.