Since I see all the threads about Blade of the Ruined King being so gold efficient...........
I have a possible solution a lot of different problems that can all be solved with one change:
This is a copy-paste from a previous thread I commented on, and please leave constructive feedback, since this is a change they COULD do but they probably won't do.
They can literally solve that problem by making it so that damage done by items is not affected by armor pen.
For example:
You have a BotRK, and you are attacking someone with armor (I'm lazy and don't want to do math). Now let us assume that armor pen doesn't apply on item effects and that the target you are attacking has 3000 hp and 50% dmg reduction from the armor he has. The passive does 8% of the targets hp, so 8% of 3000 is 240 dmg. After this is calculated, then have armor take 50% off that, which is 120 dmg (jk on not doing math). Armor pen doesn't apply in this case, so this would solve the issue of having being shredded by someone who is supposed to kill health-stackers faster as someone who stacks armor, like rammus.
On the second case of the active on BotRK , you would have the same circumstances as above, except that it would do 10% of your maximum health. Let us assume all that is in the above case. 10% of 3000 would be 300, which would then be reduced by 50%, which would end up doing 150 damage instead.
Don't you agree that this is kind of the problem?? This changed would make armor/magic pen less annoying to deal with because of how a lot of characters get damage from items, like the devourer enchantment on jungle items or the above example.
Also if you are assuming that I am also referring to the other stats that it would give, like ad, then it would only affect unique passives, because if ad you get was mitigated by armor that isn't reduced by armor pen would be kinda weird.
TLDR: Basically make item damage from unique passives not affected by armor or magic penetration. Buffs to items adversely affected may be necessary. Also to mention that if a passive lowers armor, like Black Cleaver, it would affect these items that are changed because it is armor reduction on the enemy rather than armor penetration on you.