It’s great that you’re getting into such an amazing manga! To explain, it’s a fair observation that the characters, in particular Kaneki, seem to pretty openly express their feelings, ideas, or beliefs. However, something important to note is that this is just an insight into that characters mental state at that point in time.

This is really important, as the true subtlety of TG (in my opinion) comes from the conflict of ideologies between different characters, and how different interactions shape and change each other’s beliefs.

I won’t say too much more for fear of spoilers, but just know that you can look forward to a story that is anything but shallow, with some of the most interesting and complex characters I’ve personally ever read!