I think you're forgetting some highlights of the 1970s Larry, like Mariner X's flybys of Venus - which gave us those amazing UV views of its clouds - and the detailed study of the planet by Pioneer Venus. Sure "Magellan" RADAR-mapped the place, but its work was really only an extension of the Mariners and Pioneers.

Dunno if a big flag-ship mission is really worth it without a long-lived high-temp rover to investigate the geology on the ground. More "Venus Express" and "Venera" style missions really won't tell us much more. Zeroing in on possible hydrous mineral outcroppings is needed to determine the history of water on the planet - that's one big mystery worth studying.