Should Cleanse be buffed?
Currently Cleanse is being used in less than 0.1% of games [stat from LoLKing.net]. Meanwhile items like Mikael's Crucible and Mercurial Scimitar are becoming more and more common in games.
There should be some reason to take Cleanse over another summoner spell. Right now there is literally no reason to take Cleanse over Quicksilver sash. I mean here are the things that Quicksilver Sash can remove that Cleanse can't.
- Grievous Wounds

(The slow part, not the damage reduction)
Hemorrhage
Moonlight Debuff (The part after her Q where if she ults you she gets the reset)
Chum the Waters (Drops the fish on the ground)
Ethereal Chains (break them before they snare you)
Nether Grasp (Suppression broken, still does damage if you're in range)
Children of the Grave (No Ghost for you)
Soul Shackles (Both the stun and the chains)
Paranoia (He can still dash to you, but the vision debuff is removed)
Diplomatic Immunity (She doesn't deal bonus damage to you)
Hyper-Kinetic Position Reverser (You won't swap spots and the suppression is broken)
Hemoplague
Infinite Duress (breaks suppression, still deals damage if you're in tether range.)
Time Bomb (This leads me to believe you can also remove Tristana's bomb although I don't know for certain)
Death Mark (He'll still have the shadows, but you won't explode)- It will remove almost all other DoT damage from abilities.
So why is none of the above things included on Cleanse? At lease make it remove all forms of crowd control, because currently it can't even remove a suppression.