Don't worry about locals to explore, there are many towns and villages and many landmarks to find and explore (ruins, temples, giant statues of deities, giant waterfalls, twin mountains, just to name a few). Absolutely no worries there!
There are some scattered caves yes, but most of these caves have shrines in them. But for the most part, there are not caves all over the place, which was one of the complaints by fans. But, that doesn't hurt the game by any means. And just the areas were the shrines are hidden are so unique and varied. They feel naturally placed within the game world as part of the world itself. Finding a shrine and the area surrounding it feels exhilarating, because you've gone off the beaten path, maybe even climbed an entire mountain or explored a bunch of ruins, gone into a hidden cave and found a shrine at the back!
Apart from the 4 main dungeons, it's all about discovering/finding the shrines...being able to go anywhere you want. The freedom to do anything in any order you please. And there are over 100 shrines hidden throughout every inch of the map, hidden in secret little places all over the place! You might fly down the back of a giant mountain and find one, you might walk through a cave with a giant waterfall and find one, you might walk through a ruined city within a lost ravine and find one, you might find one at the very top of a giant snowy mountain, you might stumble upon one in the middle of the ocean, of which you have to sail to and so on!!
So their placement feels very natural and organic and a wonder to discover within this engaging world they've created. A true sense of adventure imo! Also, being able to glide off of any high place, hills, mountains, with the glider is very fun!
The problem of repetition in Skyrim:
Going into the ruins of Skyrim got very repetitious, after a while. You would start to notice the same patterns, the same layouts used in previous ruins/caves.
BotW, shrines are always found in different locations that seem varied. And while the templates/design of the interiors of the shrines might seem the same, the "puzzles" are always different each time.