I have used a 42/26 or equivalent bottom gear for decades, and it still serves most of the time, but for the steepest local hills I do appreciate the granny ring on my mountain bike, the lowest gear of which is currently 1:1 (28/28 with 26" wheels = 26 gear-inches).
One of the Carlton's prior owners put a 144mm BCD Sugino Mighty Compe crankset on it, which restricts me to a 42T (or very rare, hard-to-find 41) inner, unless I triplize it. My wife's sister put a 14-34 5-speed freewheel on it with a SunTour VGT derailleur to handle the hills of Laguna Beach CA.
I am currently thinking something like 46-42 up front with something like a 6- or 7-speed 13-30 in back. That will give me 96 gear-inches, which is all the top end I have on most of my road bikes (46/13 or 50/14) and a tolerably low bottom gear, with decent ratio progression if I pick my cogs right.
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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