I highly recommend DDO. (Dungeons & Dragons Online) Even if you're not a fan of Dungeons & Dragons.
It used to be a P2P game, so it's a very very high quality. The "Item Mall" is sort of like you described, mostly fun or cosmetic stuff, though some extra quests are available. You can get a lot of "favor points" to spend in the store just by playing the game though.
The combat system is unique and requires active participation, unlike many MMO's. Character customization is very deep, and you can take any class a number of ways providing you make a "custom class." This allows you to select all traits and abilities you begin with, as well as selecting more as you level up. With a custom class you can also mix as many as three classes into one character, if you wish. So you could get abilities from a Paladin, a Fighter and a Barbarian for examble, but you'd have to sacrifice the best abilities from each.
Edit: Also, their priest type class is a lot of fun. Cleric. On top of being healers they're also sort of "Undead killers." They wear heavy armour, and generally wield a mace and shield. They get your normal healing spells and buffs, and then you can also choose to get some light based attack spells, a couple of summon spells, and so on. They also have an ability called "Turn Undead" which has a chance of instantly killing all undead within a certain radius.
Edit 2: You also begin on a newbie island which teaches you the basic. The community is probably one of the best I've ever seen on a F2P game, very friendly and helpful.
Edit 3 (Sorry): While it's not entirely new, they did recently upgrade the whole thing when they switched it to F2P. It's more than a match for recent F2P games, and even some P2P ones, due to its history.