Ruby Sightstone - level lock it ala trinket upgrades, then buff it to be gold efficient

I linked some of the comments on reddit that spurred me to think briefly about this above. I'm not a redittor so I'm going to open up a parallel discussion here.

I grok the feeling of creating required purchases. I'm curious to know other people's opinions on the idea of level locking the ruby sightstone to 1. delay the onset of any 'required' items out of the early game, and 2. allow balancing of this item to revolve solely around the late game so cool utility can be added to the item that might otherwise be oppressive and/or binary in the early phases of the game.

The level lock and the actual benefits of the item are entirely up in the air, but I feel that the higher the level lock is the closer to or above 1 to 1 gold efficiency can go. Secondly as a support based item I am going to throw out a crazy idea here -- we all know supports get boned on levels all the time, especially when behind; trinket upgrades are level locked by individual champions, let consider level locking the ruby sightstone by the highest champion level on the field. (aka, if the level lock is 15 and the enemy shaco is level 15 and your taric is level 11, taric can still buy the cool item.) (this is similar to time locking things like baron at 20 minutes but should provide more consistent unlocking of itemization options for supports relative to carries item builds.) Third a high level lock would hopefully force out other classes poaching a ruby sightstone because they would have more pressing itemization needs by that point of the game. (do you really want to spend 1600 gold on a sightstone at 30 minutes into the game when you actually need to finish that last whisper/void staff.)

So people's thoughts?