The official Lego Friends sets can be a bit limiting. They are completely rooted in a city theme, with no signs of expanding into the other Lego themes (Pirates, Space, etc.) A great way to work around this is to create your own Lego creations. One of the best features about Lego is just how modular the pieces are, almost every Lego part can be used with another Lego part. Mark Stafford used his imagination and created a sci-fi themed Lego Friends mecha titled the Ultra Violet. The best part of these MOCs is the innovative use of obscure Lego pieces. Check out the pink baskets, lipsticks, telephones, lightsaber beams, and wood panels. Check out the Friends section for more examples of this.
Ultra Violet, by Mark Stafford, can be viewed here: https://www.flickr.com/photos/nabii/6812390569/