Let us relearn moves from past evolutions.
This would be a nice thing to have so we don't need to make a whole new comp just to have a move from the past evolutions your pokémon has.
Per example, I have a mainly Physical Arcanine which was made way before the split, however with Crunch now being Physical it would be a nice move to have, but Arcanine can't relearn it and Growlithe can, so I would need a whole new comp just to get Crunch which kind of sucks IMO.
There are other examples, like if someone has a comp Slaking but now he wants to get Fury Swipes(call it gimmick, whatever) he also needs to make a new one just for one move.
I'm sure there is also other situations but I'm kinda lazy to research what pokémons would benefit from it.
I think there is no problem with this idea, it would just slightly reduce grinding(which needs to be reduced IMO).