Visually speaking, I love this pack. The new furniture and CAS items are fantastic, and they have a very cool, artsy feel. A good amount of new clothes and hair, as well as two new traits and a new aspiration comes with. I love that there's a keyboard (as opposed to the huge grand piano that comes in the base game) and a few new skill items like it. There's a decent amount of new content to personalize your Sims and decorate their space.
It also includes a new city, San Myshuno, that has a slightly different style to the three base cities. This introduces apartments, and apartment living. The neighbor relationship really works here, and I love the way your Sims interact with their fellow apartment dwellers. The city also introduces festivals and fairs. This adds some more interesting social activities for your Sim to participate in. It reminds me of the Seasons expansion in Sims 3 in that way. Pretty cool if you need to get your Sim out and about.
Overall, it's a great addition to my base game.