AP and magic pen

I'll start by saying I understand this is PBE and subject to change at any time. This is posted in hopes that Riot sees it and takes it into account.

I believe that the amount of magic pen VS trade off for said pen is highly unbalanced. With old Void Staff and Morello's you were having to trade high AP values for the pen. With the new Ludens and it's mythic passive you don't have this problem. Ludens gives a high amount of AP and Mana, and on top of that some Ability haste. The problem is the Mythic passive. With a build of Ludens, Void Staff, and Sorc Shoes, you can get 33 flat pen and 40% magic pen. 10 flat from Ludens, 5 flat from mythic passive, 18 from Sorc Shoes and 40% from Void. That is 2 items and boots giving 180 AP 300 Mana 10 haste and all the mentioned pen.

On top of this, you can also take the rune Legend: Destroyer gaining 20% bonus magic resist pen (does not apply to base MR only bonus MR from items, runes, and abilities). The rune Sudden Impact also grants 8 flat pen if you can dash.

On top of all above pen, if a tank builds liandrys and Abysl mask they will shred 25% magic resist 2 separate times, making other friendly magic dmg more effective.

If you (for example) Diana have a amummu teammate whou builds liandrys and Abysl, you will be doing near true damage to an entire team even if they are all full MR tanks. Ammumu ult plus Diana ult would be a 2 man teamwipe with both champs having only 2 items and boots in Diana.

Its my opinion that this is an insane amount of Pen and dmg at the moment and hope it comes down by a significant amount or add tradeoffs to getting all this Pen.