So, we have a new expansion and although it comes with 28 slot bags, the pattern will take some time to obtain and the increase in bank space will be rather limited. Ghostcrawler tweeted admitting that the whole inventory system seems outdated at the moment.
I mean how many of you have as many or more items bouncing in their mail as they have in their banks and bags? It feels almost like an abuse of the mail system, but it's by far the cheapest way to store materials.
With the new expansion, we also have new armors. Transmogging was a great addition to WoW, but it means people keep even more gear around, because armors can be useful as transmog templates long after they're no longer viable as armors. I think most people expected a new void storage tab or something like that, but it seems void storage was just a way to reuse the keychain space and once it was gone, that was it...there's no more.
You know what's odd? People have huge gmail accounts and videos on Youtube and compared to those, the amount of space our banks and items take is minuscule. Of course big services like Facebook are built to scale and the time-constraints might be somewhat different. It could be that game servers are highly optimized and because of that, each player has a very limited budget for storage. However, things in Void Storage are accessed very rarely, so there's no reason such items need to be part of that storage budget.
Assuming the system architecture is what it is and can't be changed quickly, what things could be done to help out with the "bank space crisis"? Here's a few ideas:
1) All archaeology and world event vanity items (keg ponies, etc) could become bind on account, so that they could be mailed to alts and kept there until needed.
2) Old quest rewards could be accessible from a vendor in exchange for justice points. The vendor could be similar to a guild page and the items on sale would depend on where the vendor was summoned. So, if I summoned the vendor in Shadowmoon Valley, I would be able to obtain quest rewards from quests that were located near that area. Having to pay justice points means that the items are available, but they aren't exactly "profitable" to obtain. This also puts players out in the world, looking for locations where they got nice quest rewards. It would also be a nice new way to use justice points.
3) Tier set collections. The implementation of this would be similar to void storage, except that you could only store tier items for your class and only one of each, with no enchants, gems or reforging. So, whereas void storage reduces the storage space of an item to a integer ID, tier set storage reduces the storage space to to one bit per tier item.
4) Better use of the currency tab and quests. Why do we still get tokens like the lesser charms and darkmoon trophies in our bags? Sure, you can opt out of the Darkmoon stuff (saves you a bag slot) and the trophies are only there while you have the quest. So why not have a counter in the Darkmoon quest?
#1 should be pretty easy to implement unless there's some kind of limitation on what types of items can be BOA etc. #2 would take some programming, but it would be a good addition to the game. You essentially need to create a database that has the locations for all the items and then you need to have a vendor whose inventory depends on the summon location. #3 is also quite a bit of work and complicates the UI, but it's the most compact way to store items that a lot of people like to keep around. #4 should be pretty easy to implement, but doesn't help all that much.