One can make, or ask a skilled player to make, level 70 leather armor pretty easily. Amazing skin can be farmed solo at level 60, and is most likely sold by players anyway (I have stacks of them on my vendor). So, even if it's hard to acquire dropped level 70 gear solo, and can testify it is unless you've specialized in cold environment survival, grouping the entrance of Gazluk Keep with leather armor is in my opinion possible, and from there you get all the loot you want. What you need is a decent reputation and basic fighting skills, so that people will assist you to make the armor and accept to group with you. If you want to do it all by yourself, then yes it's definitely much harder.

Regarding the storage issue, one need to stop hoarding and sell/buy all these mats: only phlogistons and prisms really need to be stored, and there is no point keeping all levels, only the two level ranges that matter when you transition at 30 and 60.

(Disclaimer: I'm well-geared and don't have these problems anymore)