Luden's Echo Has Changed the balance of the Game

I don't think that Luden's Echo was a balanced trade off for Death's Fires Grasp. The potential problem that I have witnessed is with champs that spam spells. DFG let you hit 1 target and reduce their mag res for a time...and this was toxic...apparently why it was removed. Now there is an item that lets spell spammers run rampant. Let me explain...Luden's Echo get's charges with spell casts and movement once at 100 charges the passive goes off and gives extra damage on the next cast. In my opinion this has unbalanced the game. A couple good example's of champs that are overpowered with it are Katirina, and Le Blanc. It's has definitely in my eyes reduced counter play. It was not a bad idea but I seriously believe it needed more refinement before being added. I don't think there was enough consideration of spell spamming champs before it's introduction. I believe either Luden's Echo needs a nerf or rebalance the stats of spell spamming champs. Obviously, altering Luden's Echo would be the quicker fix.