Video service delivery over 3GPP Long Term Evolution-Advanced (LTE-A) networks is gaining momentum with the adoption of the evolved Multimedia Broadcast Multicast Service (eMBMS). In this paper, we address the challenge of optimizing the radio resource allocation process so that heterogeneous groups of users, according to their propagation conditions, can receive layered video streams at predefined and progressively decreasing service levels matched to respective user groups. A key aspect of the proposed system model is that video streams are delivered as eMBMS flows that utilize the random linear network coding principle. Furthermore, the transmission rate and network coding scheme of each eMBMS flow are jointly optimized. The simulation results show that the proposed strategy can exploit the user heterogeneity in order to optimize the allocated radio resources while achieving desired service levels for different user groups.