In intermediate water depths (100~300m), an array of floating point-absorbing Wave Energy Converters (WECs) may be employed for extracting efficiently ocean wave energy. In such case, it may be more feasible and convenient to connect the absorbers array with a semi-submersible bottom-moored platform, whose function is to act as the seabed. An array of identical floating symmetrically distributed cylinders in a coaxial moored platform is proposed in this study. The Power Take-Off (PTO) system is assumed to be composed of a linear/nonlinear damper activated by the buoys heaving motion. Linear hydrodynamic analysis of the examined floating system is implemented in frequency domain. Hydrodynamic interferences between the oscillating bodies are accounted for in the corresponding coupled equations. The array layouts under the constraint of the platform, incidence wave directions, separating distance between the absorbers and the PTO damping are considered to optimize this kind of WECs. Numerical results with regular waves are presented and discussed for the axisymmetric system utilizing heave mode with these impact factors, in terms of a specific numbers of cylinders and expected power production.