Design Space Exploration (DSE) of programmable systems-on-chip (SOC) incorporating parameterizable processor cores is difficult due to the complex and intrinsically non-structured interactions between different architectural features of the processor (such as wide parallelism, and deep pipelines), the compiler and the application. Changing different processor features implies generating detailed operation conflict information - represented as Reservation Tables (RTs). If done manually, it can be a very tedious and error prone task, especially for deep pipelines, with complex resource sharing and large non-structured instruction sets.In this paper we use RTGEN [2], an approach for automatic generation of RTs, to drive rapid architectural exploration of a large number of designs. We present exploration experiments on a large set of VLIW-like EPIC1 architectures, for varying port sharing, number of functional units, multicycling units, and with varied latency configurations. Our experiments uncovered several non-intuitive architecture design points, giving the system-level designer further flexibility in exploration of programmable SOC architectures.