Why No Mundo Nerfs in 6.1? (and more)

Everyone agrees that Mundo is in a state right now in which his toxic skin should replace his base skin, yet he remained unchanged. I'm just curious as to why. Even tiny nerfs like reducing the damage on his cleaver by like 2% at rank 5 or chipping away at the regen on his ult or giving it a longer cooldown (10 seconds more) would help. I was going to type a lot more on how lane bullies are a good idea but they ruin the game for their opponents and create a stressful and toxic environment, but I accidentally closed this tab twice and am annoyed.

Also, can someone fill me in on the Leblanc buff? I don't understand it. To me, Leblanc is a low risk high reward champion that works extremely well right now, especially with thunderlords. Her spells have a high mana cost and she has a relatively small mana pool but she can kill people with just 2 rotations so it doesn't really matter. Her mobility is unrivaled so if you depend on skillshots and have no hard cc you're just kind of stuck, and she can escape most ganks easily. She can also dive pretty easily, only taking one or two turret shots and then w/r back. People say she falls off late game, but she can instakill carries just the same as any other ap carries. Do they say that because she has no utility? Lastly, people say she cant deal with tanks. No burst mages can deal with tanks right now. Literally full magic pen runes, sorcerers shows, liandrys, abyssal, and void staff can all be negated by just a banshees veil. Liandrys doesn't work well for people like Veigar or Leblanc anyways.

In the end, I'm not trying to complain or whine about any of this, I'm just trying to get a clear understanding of what higher tier players or riot thinks about her weaknesses. My opinions aren't set in stone, and I have an open mind hoping some of you will help me see other viewpoints. ALSO I DON'T LIKE HER DANCE