@Riot how about an ability for a future Champion that consumes mana/sec to Stealth?

I'm going to write MUCH more on this later as I've previously written 50+ paragraph essays on Stealth on the old forums (yes really) and how it's problematic in different degrees, but for a quick writedown for now, I was thinking that an ability that drained mana/second would be a good way to balance stealth, as it creates time and resource constraints on when it can be used. Alternatively it could even be drained from another resource (energy/fury-ish/etc) to work similarly.

Anyhow, I'll write more up on this later as I wanted to get this out of my head before sleeping, but at the very least I'd like to see the community's initial reactions to this idea.