As far as the doing what's comfortable argument goes: What's been comfortable for you while riding alone might not apply when you find yourself riding with faster riding partners. That's when some people find a need to adjust to a different cadence when they run out of steam mashing the heavier gear to keep up. There is an adjustment period, as a vaguely recall
. But once you stop getting winded at the higher RPMs you might find the right niche for your riding style if you've been having trouble running out of steam keeping up with partners on the heavier gears......ymmv depending on your personal physical makeup.
That was kind of my experience as I began road biking 35 years ago.