In the context of a competitive 5G environment, satellite systems must be able to provide cost-effective solutions to complement terrestrial networks. In a preliminary paper, the achievable capacities of diverse LEO satellite payloads were computed as a function of a parameter characterising the non-uniformity of the users distribution in the satellite field of view. As the non-uniformity parameter increases, the capacities of the various payloads benchmarked decrease because of inter-beam interference and shortage of frequency resource. A way to mitigate this capacity loss is to use flexible payloads with adaptive capabilities such as beam steering or flexible resource allocation. This paper proposes to extend the study to MEO payload and antenna architectures and benchmark them with respect to the capacity they can achieve and the power they require. A Circular Direct Radiating Array with Digital Beam Forming, a Sparse Direct Radiating Array with Digital Beam Forming as well as an architecture implementing Hybrid Beam Forming are analysed in terms of effective capacity achieved on different scenarios of users distributions with varying non-uniformities. The application of these results on a realistic scenario of user distribution concludes on the most promising payload architecture.