The goal was to design a spaceship that might be produced by "Corellian Engineering Corporation" (Millennium Falcon is one of the spaceships manufactured by CEC) but as next generation series, maybe in 50 or 100 years after Millenium Falcon was made. Something that has similaryties in design language but based on new plating design solution new materials and tech, still looking heavy, rigid and industrial but one step more advanced.

Ford Mustang from 1960 comapring to one from 2010 might be a good analogy.