Just a random thought: This class doesn't seem very "primal." It's a cool concept and a cool name, they just don't fit together perfectly in my mind. More a flavor nitpick than anything.
So can ... normal combat magic. Wail of the Banshee kills you. Dead. And it kills all your friends. Cloudkill + Forcecage kills a Fighter of any level, bar magical gear. Dominate Monster kills you AND gives your opponent a free minion. Mass Charm Monster turns you and all your friends. Finger of Death kills you. Hold Person lets a rouge dismember you. Magic in generally is brutally lethal, even if you don't chainbind, abuse wish, or create antimatter.Yeah, unlimited uncapping can be really strong.
Sure, most of those things allow saving throws, but they don't allow energy resistance. They're also bad design (in combination with the boring 3.5 Fighter) because it means fighters and wizards don't have any synergy.
But that doesn't matter, does it? Ray of Frost could do 40d3 (a 4000% increase) and it still wouldn't be worth casting - even against a red dragon. The reality of high level combat is that things die in one round. Two tops. If your class can't do that, it isn't competing.a 20d6 Shocking Grasp at 20th level is a 300% increase.
You might (I'd have to runs some calcs) be able to not only uncap, but also double the dice and have fair damage. But that's way, way too many dice. I recommend changing damage expressions to involve a fixed factor (like 2d6 + 14 rather than 6d6), but that might be a bigger overhaul than you want. Also check this out. That's a simpler, and probably equally effective fix (expect for ninth level evocations).
Why not just make conjuration blasting evocation blasting then? I always thought the orb spells should be evocation anyway. .Unfortunately, it also makes conjuration blasting more useful too, at exactly the same rate, which is not exactly ideal.