Interconnection networks are one of the main limiting factors when it comes to scale out computing systems. In this paper, we explore what role the hybridization of topologies has on the design of an state-of-the-art exascale-capable computing system. More precisely we compare several hybrid topologies and compare with common single-topology ones when dealing with large-scale application-like traffic. In addition we explore how different aspects of the hybrid topology can affect the overall performance of the system. In particular, we found that hybrid topologies can outperform state-ofthe-art torus and fattree networks as long as the density of connections is high enough-one connection every two or four QFDBs seems to be the sweet spot-and the size of the subtori is limited to a few nodes per dimension.