Hextech crafting - Possible champion shards "sink"

I've seen a lot of people complain about earning champion shards while having already all the champions, so i've got an idea how to deal with it.

Simply, whenever you find a champion shard in a chest, you can disenchant it, and you get an option to disenchant it for it's original value of champion essence (roughly 33% of the permanent item price, if i remember correctly,) or disenchant it for the cosmetic essence, for half of it's original price (For example, if you disenchant a champion shard for 300 champion essence, you will earn 150 cosmetic essence for disenchanting it for the cosmetic essence).

Looking for opinions and comments about this idea.