Option
#1 should replacing that Regina freewheel with a Japanese 6- or 7-speed, which will have a more shift-friendly teeth profile. Replace the chain with a good SRAM "8-speed." If you are still unhappy, replace that parallelogram derailleur with a SunTour. (The Campag. front should be fine.) Route the rear brake cable over the handlebars.
GREAT looking bike, by the way, and I am not surprised you are pleased with the ride quality.
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"Far and away the best prize that life offers is the chance to work hard at work worth doing." --Theodore Roosevelt
Capo: 1959 Modell Campagnolo, S/N 40324; 1960 Sieger (2), S/N 42624, 42597
Carlton: 1962 Franco Suisse, S/N K7911
Peugeot: 1970 UO-8, S/N 0010468
Bianchi: 1982 Campione d'Italia, S/N 1.M9914
Schwinn: 1988 Project KOM-10, S/N F804069