Does the word "wonderful" is somewhat related to "full of wonder"?
You are absolutely correct. The word "wonderful" was originally used to mean that something or someone was “full of wonder.” However nowadays it is not often used in that way. These days "wonderful" is most generally used to mean “extremely good” or "amazing" rather than "full of wonder". Ex: This meal was wonderful. Thank you for cooking. Ex: I just had a wonderful vacation. Ex: It was wonderful seeing my family at Christmas.