I think half the reason this game has gotten so hilariously unbalanced now is because Rito has started heavily focusing 90% of the balance changes around LCS
I mean right now theres champs who were OP in competitive so they got heavily nerfed to the point where theyre unplayable to lower ELO players, and if you try to pick them at all you're considered a troll
theres champs that are so OP that if you dont either pick or ban them you're instantly considered to be a troll, some intentionally being kept strong simply because they look flashy in pro play (looking at you, Lee Sin.)
Assassins can get upwards of 60% MR with a spellshield now without sacrificing damage because guess what, MR is tacked onto so many AD items now it's getting silly, and mages still basically only have 1 magic pen item worth getting and thats Void Staff. (if ur gonna try to say that Liandry's is a good magic pen item ima smack u and the boots are so core for so many mages its not fair to count it)
Honestly the gap between Mpen and lethality is nuts right now, mages get next to no magic pen and only have 1 ap/armor item that is a shell of its former self while AD champs are swimming in AD/MR items that have good stats and amazing passives/actives, its honestly unfair for AP champs nowadays.
Masteries are still massively overtuned, especially keystones. A lot of people used to go hybrid mastery builds with the old masteries, without getting the final mastery in any tree. Masteries used to be more diverse with a hell of a lot more options, now most champions are forced to go to a certain tree and only really have an option between like 2 keystones, and if you try to go hybrid now with no keystone, youre considered a troll.
Damage creep is through the roof now with nothing being done about it still (I doubt those small mastery nerfs will do anything noticable at all.
Almost all the changes in the past couple years were aimed at making LCS games shorter and more action-packed, but it really just made a stale viewing experience where, past the 20 minute mark, both teams play extremely carefully because one single lost fight (god forbid if its an ace) can cost a full lane of turrets and usually an inhib too.
I think a lot of things need changed back tk how they used to be, and that champion BASE damages need to be GLOBALLY reduced by about 20% to address the insane damage creep.