That is one sweet looking bicycle. I bet that saddle is ultra comfortable. ?
How long have you been back bicycling? Over time one of two things will happen.
#1 . your cadence will increase
#2 . your stamina will increase even though your cadence stays the same. Sometimes in exercising it's best to "make haste, SLOWLY".
I'd ride the bike for a few months at least to determine what needs aren't being met. Changing the rear cog to a bigger one will give you overall lower gearing as would changing the chainring to a smaller one.
Do you plan to tour on it? Some people tour on bicycles that they push up hills when the hills are too steep for the gearing the bicycle has. Many of those people like the break in the riding and the fact that they can take in the scenery more too.
Cheers