The Hollow Knight Defender has logged on.
Here are the things I think Hollow Knight does better than almost every metroidvania.
-It Lets you get lost and asks you to familiarize yourself with the world. It does so with the map mechanics, including the compass charm - the fact that it’s not free subtly suggests “hey… what if you simply learned the world well enough to not need it?” And then you do that, and it’s a “free” charm slot!
I love any game that has me staring at the map to figure things out. (I’m thinking about Tunic)
The fast travel mechanics eventually lessen this effect, but they are also quite limited at the start.
-Reaction based combat, especially bosses. There’s a lot of them and they feel challenging yet fair. That’s because they typically have few attacks (memorizable) and you have the tools to overcome them (no inertia on sideways movement, instant attacking and dodging).
The magic system is an amazing design, every game copy it please. You can always refill it by hitting enemies, so you can explore and fight forever if you do good enough, unlike for example running out of Estus in Dark Souls. The fact that healing is a long action, unlike attacking, adds an extra dimension to fights where figuring out windows to heal is important (in Dark Souls, if you have time to attack, you probably also have time to heal)
The fights allow for a lot of skill expression. If you’re not taking damage, you can instead use your magic for offensive spells and there are details like parrying or hitting projectiles back that add even more.
All that being said, it starts very slow and it is hard and punishing in some weird ways. Let me mention Dark Souls one more time to say that dropping your money when you die and having to run back to the boss sucks, they didn’t need that part!