Addressing storage in GW2 is tricky because of the fact that it can be extended via the game-store. However I believe the developers should be conscious that many players will not be willing to use the gem store to do so and will still expect to maintain a certain capacity of storage if they plan on continuing playing at all.
I believe that the time to increase the games base storage limit has come. Although for the sake of the gem-store there are some ideas of how it can be done without changing backpack or bank limits.
1. The amount of back pieces and head-slot items from events is outrageous. I believe these items should be made infinite use and placed in a collection tab
2. Every character should have multiple tabs of armor. Maybe they have an separate set of armor for dungeons, wvw, etc. A second or third tab of armor can be selected just like the town armor.
3. A new type of collection tab for items that can stored but still used w/o removing and placing the item back in your bag. Items such as potions and boosters which can overwhelm your inventory and switching between toons is tedious.
4. A place in your armor tab to place food and other consumables which once placed has an option to auto-consume.
5. Portable crafting tables for lvl 400+ crafters; to refine crafting materials at which are already full in bank/inventory.