Proposed research framework aims at generating computerized conceptual product designs by incorporating Modularity, Design for Assembly (DFA) and Design for Variety (DFV) principles at the conceptual design stage. Conceptual design alternatives from the proposed framework are ranked based on minimum assembly time and are composed of modules in a way that future changes in customer needs are satisfied only by replacing certain modules. The framework involves searching a design repository of components by using functional-basis and pre-defined graph grammar rules, to generate all possible conceptual design alternatives. These are ranked and filtered using a DFA index, and top two alternatives are selected. Selected designs are modularized and filtered using a DFV index to obtain the best design alternative. The proposed framework is demonstrated through the design of two electro-mechanical products.