@Riot: Any Chance for Spellvamp to Make a Return?

I understand that spellvamp has been problematic on certain champions before (see: Vladimir), but it's a really interesting stat and it's incredibly disappointing to me that it was completely removed as opposed to simply being reworked.

I imagine there are plenty of ways to rework spellvamp into something that isn't toxic. One way could be that it simply doesn't heal or has a significantly reduced healing on spells that cost health or spells that already heal, which would keep Vladimir and Cassiopeia from abusing it.

For example:

Will of The Ancients 80 ability power 10% cooldown reduction Unique: Abilities instantly heal for 15% of raw magical damage. Area of effect abilities only heal 5% for every unit affected. Spellvamp does not apply to self-healing abilities or abilities that cost health.

What are your thoughts on the prospect of spellvamp returning, and how do you think it could be balanced if it were to make a return?