Suggestion for Liandry's Balance (that small push to bring it back to relevance.)

For quite some time Liandry's has been an okay item. It gives mediocre stats and a fun, but lackluster passive, as well as flat magic penetration. It fits into some builds as a niche item, but still seems to fall short in some categories, in my opinion. From what I have seen of LCS, those layers agree as well, as it's not played very often if at all in these games.

I was looking at several items that many champions have access to, with the same niche placement, that just felt they did more for the champion that built them. Wit's End and Black Cleaver are the primary things that came to mind. I was looking at Liandry's in the same light, and thought of a way that this item could perform at just a bit higher tier, and more importantly FEEL better to play.

Mages currently don't have their version of Wit's End, to slowly ensure their spells do damage into late game and through the duration of an extended fight. My suggestion is that Liandry's becomes the mage's version of that item. As it burn's it's DOT, it could shred the opponent's MR slightly, but over a long duration. I haven't done a whole lot of math or anything, but an example could be, the DOT from Liandry's reduces MR by 3 per second it burns, up to a maximum of 30. That's 10 seconds in sustained combat to get maximum effectiveness, which means it doesn't bump assassins up the list, but it gives mages that are currently harder to balance an option for dps. Champions like Cass, teemo, and Rumble could have another option to actually add successfully to their kit for laning against tankier, sustained damage opponents. Another option would be the Cleaver route, and have it shred 3% bonus MR per second, up to a cap of 30%, which further boosts dps mages, while lowering the capacity for abuse by assassins.

I am fully up to recieve positive and negative feedback, this is simply an idea I wanted to pitch to Riot, because I feel it could make a positive impact in the game and meta.