Rage skills almost useless for Soothsayer?

[Zechnophobe]

Wall and charista's gold are both solid for soothsayer. The control style effects always are.

Also Gurlda's rage (fiery one) deals percent fire damage if you ignite, which makes it good (for everyone).

[Loopy]

I haven't unlocked more than the first 4, but obviously damage is always useful.

Ice blades have been incredibly useful to protect my units so far.

[Nevar]

I barely use wall, really. I'm usually more concerned about the ranged units, so the wall doesn't do much for me.

I admit the burn is nice, although you could probably get more mileage with Olaf's skills if you manage to get Icy Rage to at least level 2. Freezing is amazing.

Also, in the late game, the damage you can do with Rage Skills is probably going to be practically nothing compared to your damage spells. I really hope one of those last two Rage Skills does % based damage or replenishes Mana.