Sight Stone Upgrade

There's a lot of talk about wanting a Sightstone buff.

What if you give it the Devourer treatment where transforms to after you place a certain amount of wards?

Placing a ward gives you a stack of Rift Sight. At X amount of stacks, Sightstone transforms into Ruby Sightstone. You can only gain a stack of Rift Sight every X amount of seconds

That would make it so they can't abuse sitting in a fountain and placing wards.

I know it's not exactly a crazy buff or anything new to the game, but it would save supports the 800g theyd use to upgrade it.