The Rebels appeared to have an actual industrial base. They were able to muster a substantial fleet against the Imperials at Endor. Now given the economies of Star Wars, maybe giant starships with hyperdrive and turbolasers aren't that big a deal (the equivalent of Somalian speedboats

) but they seemed to be commensurate with the Imperials whom we might presume had far greater resources.
Of course, we need not--heck, half the galaxy might have risen after Yavin. It's not like anybody other than the Imperial Navy and Army themselves actually believed in Palpatine's leadership, and that was because of the Force if I remember the novels correctly.
I actually prefer to think of the Rebel Alliance as a highly organized structure who had graduated from spectacular annoyances in X-wings to conventional warfighters. Guerilla warfare doesn't usually work that well against an enemy willing and able to obliterate your planet from orbit. Trek could've taken a page from this.