AN EASY WIN ON INVENTORY
Aion is a better game than a game without the following client-side feature. It's on the corner of the inventory, a magical little button that sorts your inventory.
You can see it in the icons even if you have no idea what these items are. The rock-looking stuff is all together. The potions are all together. The scrolls are all together. Sorting goes by level -- so much more sophisticated and smooth than games without arrangement. I had to actively try making this UI look messy for the comparison below.