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A lot of my OMC twins, I measure compression and if pretty even, I don’t worry much unless really low or one is 10 or 15 psi lower than the other, which is a factory spec too. You say it runs, so no problem. I pull the head and sometimes just take 320 wet and dry and clean the cylinder above the piston. Depends on rust and other conditions. Most bores are loose at the top anyhow and not the bottom, and the bottom end give you crankcase compression. That makes for hard starting if loose. Sometimes added oil solves that sealing problem. Also the added oil helps seal the rings. The rings expand from compression, not spring pressure, so the ring gap in a pleasure motor isn’t as important as a race one. A few thousands after a hone I don’t worry much. If you get towards 0.005" and more I begin to worry. You can cheat it by a number of tricks. One is to knurrel around the bottom of the skirt which will expand that area and help to seal for crankcase compression. It helps to hold oil too, therefore more sealing. The other is to have the piston coated with a Teflon coating that adds 0.002" per coating up to 0.006". Swain Tech in NY is a good place to go for the coating. If apart, new rings don’t hurt. We all have to think how many hours are we putting on these engines in a season? And they have lasted how many years as is?
I have a whole line of 1958 blue Evinrude’s and the only thing I had to do was water pump, ignition, carb and gear oil. Sometimes I think we over think these things.
Life at 4,500 rpm is a lot different than life of a race motor at 12,000 rpm.