If I am in charge, the responsible person who makes the decisions, for example, go, or chicken out, I am the captain. And this applies to my boat, and my aircraft. Any crew or passenger who finds it difficult to understand my rank is left on the dock. I have been sailing since 1938.
As for uniform or gold bars, not needed. I do have 3,000 hours in the air, as instructor, tug pilot etc. The tug pilot pulling up a glider also is in charge of the combination, so in effect the captain, until the glider departs the tow or you dump him. Uniform in the aircraft? a narrow brim sun hat so your brain doesn't get fried; but your vis is not impeded. In the glider, I find a baby blanket stowed behind me but still in reach is good if you fly high enough to get cold; you can then be quite comfortable with the extra cover, as high as 20,000 feet over Deeside gliding club. Yes, with oxygen.
Of course a power plane is nice in winter, often has a heater.