From the update:
We are working on the basis of height for the first two goals. To gain height you need a few basic components, converters, second level clips, gantries and railing. these will compliment the two floor tiles we gave in Stretch goal 6.
First up Stretch goal TEN & ELEVEN - 3 pairs of Converters and Clips, 2 Standard Gantries, 5 Spot Lights. The converters enable you to build sheer wall faces and consist of 12 pieces including all the clips. The standard Gantries are the staple of your walkways and are also the most flexible for creating shapes, (you can never have enough of these), finally are the lights, they add the details and the 3D element that really create the look of the set and bring it all to life, just like the Struts and Buttresses do for the walls.