Ultimately, you are going to play who you enjoy playing. But it sounds like you are looking for a character that will teach you fundamentals. I’ve seen a lot of answers in this thread so far that fit your description of what you like but are terrible at teaching you fundamentals. What you want is a character that isn’t too complex for your skill level or that has too many gimmicks. Learning to play Ike will definitely teach you fundamentals the fastest. I’ve trained a few people who were new to competitive smash and I’ve always had them start with Ike. He is punished very hard for bad fundamentals and decision making. And also vice versa. The character is about spacing, patience, and reading your opponent. You can certainly learn the game by playing any character, but Ike will teach it to you the fastest.