Small claims only provides monetary relief, you can't get equitable relief. How exactly are you going to calculate your monetary damages? And quite frankly, why would Google reinstate your account over losing a maximum of potentially $7,500?
The difference between Small Claims and Superior is that in the former you're generally not allowed to bring an attorney, whereas in the latter you may actually be required to bring one.
Does anyone know whether account suspension without a reason is actually something that a pro-se litigant has any chance of suing these big companies for, and winning at all?
That only applies to individuals.
Corporations are not only allowed, but in fact required to be represented by an attorney in court. Even small claims. Corporations do not have pro se representation rights, and only an attorney can represent another person.
The thing that may be daunting about Superior Court is that the judge is supposed to take it easy on pro-se litigants, but at the same time, they are still supposed to be impartial, and can't really act as your own lawyer.