Invisibility for the Town Hall.

No, I don't think anything should be reduced. If the duration of invisibility is reduced to two turns, what's the point? You just run to the end of the map, and that's it. And if you reduce their initiative, Stalkers won't always go first (sometimes they go after Elven Archers). And if you reduce their intuition, they'll be taken out by those same archers, and invisibility will also lose its meaning. But the developers probably know best, let's see what happens in the patch (if it ever comes out).