In this paper we present a swarm grammar system that makes use of bio-inspired mechanisms of reproduction, communication and construction in order to build three-dimensional structures. Ultimately, the created structures serve as idea models that lend themselves to inspirations for architectural designs. Appealing design requires structural complexity. In order to computationally evolve swarm grammar configurations that yield interesting architectural models, we observe their productivity, coordination, efficiency, and their unfolding diversity during the simulations. In particular, we measure the numbers of collaborators in each swarm individual’s neighborhood, and we count the types of expressed swarm agents and built construction elements. At the end of the simulation the computation time is saved and the created structures are rated with respect to their approximation of pre-defined shapes. These ratings are incorporated into the fitness function of a genetic algorithm. We sh...