In the recent design of high ductile fiber-reinforced ECC (engineered cementitious composite), optimizing both processing and mechanical properties for specific applications is critical. This study presents an innovative method to develop new class ECCs, which possess the different fluid properties to facilitate diverse types of processing (i.e., self-consolidating or shotcrete processing) while maintaining ductile hardened properties. In the material design concept, we employ a parallel control of fresh and hardened properties by using micromechanics and cement rheology. Control of colloidal interaction between the particles is regarded as a key factor to allow the performance of the specific processing. To determine how to control the particle interactions and the viscosity of cement suspension, we first introduce two chemical admixtures including a highly charged polyelectrolyte and a non-ionic polymer. Optimized mixing steps and dosages we, then, obtained within the solid concentration predetermined based on micromechanical principle. Test results indicate that the rheological properties altered by this approach were revealed to be highly effective in obtaining the desired function of the fresh ECC, allowing us to readily achieve hardened properties, represented by pseudo strain-hardening behavior in uniaxial tension.