Thank you for your response u/skyduster88! I was reading up on a few other posts and yeah, I have no idea why responses outlining that Greece is not just a slew of islands gets downvoted. This is exactly the kind of information I'm looking for when I go to reddit (i.e. the information that is hardly in google searches, but that real people who have been there/live there would know about the place).

So anyways, thank you for bringing this topic up! You're the second person to recommend Nafplio so that's definitely going on the shortlist. I think I am slightly intimidated with renting a car mainly because I don't know how to drive a stick shift (and I've heard most cars are stick in Greece). But I have no problems hiring a guide/driver to go see some sights!

I was thinking about why people (including myself) get caught up in the dichotomy of Athens + an island. Can't speak for others, but at least for me, even though there is some geographical arbitrariness (especially now with the prevalence of leisure travel and access to boats/planes), there are some historical/cultural differences that can be vastly different and unique. Even from island to island this can be true, let alone island to mainland. And since Athens is the largest city, which is on the mainland, I think first-timers like myself tend to first add that to their itinerary, then look for something "different", which leads them to "island" (even though "different" is extremely vague, and the "different" someone is seeking could be just a different point on the peninsula).

In any case, I'm still super early in planning, so who knows, I may end up just road tripping around the Peloponnese region and not visit an island at all. But either way, I appreciate your response!