There are principles, such as the ones that are attached to your package. There are many sources of general principles. They support but do not guarantee consistency of decisions. There are two elements to that, I would say. There are two ways of approaching it. One of them is ongoing training within a tribunal that has national scope. The Immigration and Refugee Board and the Parole Board are other tribunals that have had this issue. They're both national. They have hearings in different cities, and they try to make sure that their members are trained on an ongoing basis.
I noticed that VRAB has an internal training unit, which is a very positive thing. I would also argue that publishing decisions is an important element. If decisions are published, they become exemplars. There is no precedential requirement. Decisions don't have precedential value in tribunals, but typically a tribunal will see how they decided a similar case two months ago or two years ago, and use that as a guide. It's precedent de facto, not precedent that's forced on them.
It's far easier to determine what precedents there are, if you're either a member of a tribunal or a member of the public, or an appellant, if the material is readily available.