Now, the Soviets actually kept flying their equivalent to the Saturn 1B - indeed, despite attempts to switch to better and newer rockets for the last 40 years, the Proton still flies. It has also barely been upgraded. Though not for lack of proposals, some of them quite extreme.
Your mission, should you chose to accept it, is to propose the most extraordinary space program you think plausible that would use the Proton as its main rocket and what the Proton rocket might turn into if the Soviets really start to tinker with the machine?