I think Veloce/Centaur/Athena is an excellent way to go (as stated previously).

Chrome pitting is generally a lost cause, however I have had good luck using brass wool and simichrome. It won't be perfect, but it can be better than it was. You got a great price on a rider frame...set it up as a rider and don't sweat the patina. I have bikes that are beautiful, and honestly it's a pain because it makes me paranoid about using them.

Dura Ace 7400 makes sense to me as a group on this bike because, at the time, it was the best group available, it doesn't look completely awful and most of us switched to Shimano during this period. Modern Shimano makes no sense to me on this bike - it's butt ugly, it's not really any cheaper than Campy, it would look less appropriate and I don't think it works as well. Modern Shimano looks terrible on classic steel.