Ok, I've noticed this argument before and it's beginning to drive me nuts. Both of those examples could EASILY kill people and the more popular one, the 'Sleep' spell is actually a canon example of a seemingly innocuous spell that will be lethal if taken to extremes in the example of Agatha Hagglethorne. I challenge anyone to describe to be a spell that, if take to the equivalent force of a Weapon: 4 attack could not possibly be lethal.
I think "could not possibly be lethal" is a bit too strong a challenge, since even a toothpick could "possibly be lethal". But I think you're asking the reverse: describe a spell that "could consistently be non-lethal".
Lightsaber Strike
Fire Evocation:
Weapon:6 Offensive Attack
Fluff: Automatically cauterizes wounds as it cuts. This could easily kill, but could just as reasonably chop off limbs and leave the victim alive.
Vertigo Wave
Earth Evocation:
Weapon: 4 Offensive Zone Attack
Fluff: Creates minor fluctuations in gravity within a zone, which play havoc with the target's sense of balance. Common consequences are "mild nausea" (minor), "motion sickness" (moderate), or "long-term balance issues" (severe)
Bacchanalia
Summer Evocation
Weapon: 5 Offensive Zone Attack
Fluff: Recreates the physical symptoms of inebriation in the target. Common consequences are "euphoria" (minor), "lethargy" (moderate), "stupor" or "blackouts" (severe)