Wide field, high sensitivity, high resolution, wide bandwidth, and polarization components are constantly pursued by CO molecular line surveys at millimeter wavelengths. Several key science cases that could be focused on by future large-scale molecular surveys have been identified upon the current progress of molecular surveys. A conceptual design for the new-generation multi-beam receiver system is proposed. Combined with the latest technical progress, the key technical solutions to realize the scheme are explained. The new design aims at a receiving scale of 100 beams. Following the newly developed hybrid planar integration technology, a new dual polarization receiving function is realized while inheriting the sideband separation mixing mode. On the basis of multi-line receiving configuration, each receiving sideband is expanded to 8 GHz. Judged from the existing technologies and the newest progress, this conceptual design scheme is fully achievable. Compared with the existing millimeter wave multi-beam receiving equipment, the comprehensive receiving capacity of the new generation millimeter wave multi-beam receiving system is estimated to increase by a factor of 89--178. This design is expected to bring another evolutionary progress for millimeter wave multi-beam receiving capability.