If Riot wants to try and change the meta
The biggest impact would be how experience is split among champions. Morde is a prime example of how a mage can overpower regular duo bots just through sheer experience differences.
I'm not saying to change anything, or that morde is not toxic, but I honestly feel that experience is what would create a new meta faster than anything.
Now according to the morde change, negating the one of two downsides of being in a lane with another champion just for that champion is complete bullocks and not a healthy way to mix things up. AD characters are already at a downside against mages in the laning phase, and giving that mage high scaling and a huge burst in a single ability make it worse