Rammus W Self Slow

I feel that the 60% slow is a bit to harsh a nerf. Rammus would fee so much better if he had a 60/50/40/30/20% self slow rank down as it gets levels put into it. As is his W feels lack luster to level up because the only thing that gets affected is the resistance % increase. The mana cost is the same, the cooldown is the same, and the base damage scales with your passive.