In this video, you'll learn many interesting words and expressions using the Kanji 意. I will explain the difference between いし and いがい written with different kanjis (意志 vs 意思; 意外 vs 以外).
Yes, you are right. Complicated Kanjis are even difficult to remember even for us Japanese But actually all written in Hiragana is quite confusing and difficult to read well. And Kanji helps to grasp the meaning of the word better.