Euhm, I would say our retainers are our "bank".
As to the primal/raid tokens you should throw them away after you get the mount or weapons you want and certainly the ones from previous expansion. Why would anyone besides a hard core hoarder hang on to them?

As to crafting materials there is little need to hang on to materials as most are relatively easy to gather or very cheap to buy. I have noticed that our own inventory is big enough to hold all materials to craft everything from one expansion if you don't count the items that are very rarely used and ignore culinary materials.