Strength of the ages is getting replaced with a new keystone named Courage of the Colossus. It's effect is: If you inflict crowd control onto an enemy champion you will generate a shield that absorbs X damage. Sure Strength of the Ages might be getting replaced with a good new keystone, but what's bad is we're losing a good keystone and keeping a terrible keystone.
Bond of Stone is just complete garbage to put it simply. If you don't know what it does all it does is this: You take 4% reduced damage. If you are near any allies you absorb 6% of the damage they would take. If you are below 5% max HP this effect is disabled. Now you hear wow 6%! That's so much, but in actuality it's not even remotely close to good. If it were something between 15-20% it'd be amazing. Being at 6% damage absorption your allies would be better off running around with doran's shields all game like bots.
Strength of the Ages being removed is a big deal because it is a very core/niche keystone mastery for junglers. It gives you bonus HP up to 300 every time you kill a large minion/monster or are near one that dies. After your each the cap of 300 you instead heal for 6% of your max HP. This is great for junglers because you don't have to worry so heavily about stacking HP mid game.
Item sets are fine, but shouldn't be a major concern for the player base because at the end of the day it doesn't impact the game in any way, shape, or form other than pure cosmetics.