First, I'm glad the comments were helpful. Second, I'm glad you're open to feedback. Sometimes people will post photos saying "critique" and what they really mean is "tell me I'm magnificent."
OK, as to the overall critique--it's less about "pay attention to the little things." Rather, it's about learning to SEE differently. My favorite all-time quote about photography is from the great Dorothea Lange. She said: "a camera is a tool for learning how to see without a camera." Look at a landscape and your eye automatically ignores the empty cokecan in the fore ground and the telephone wire in the background and the glare on one part of the windshield. You're not CONSCIOUS about them. But unconsciously the scene feels uncomfortable to you. When you get better at composing a shot you don't just pay attention to "little things." You look at it and think "is this the best angle? If I wait 10 minutes I'll get better light." And "I'll need to crop out that wall with graffiti on it." All before you click the shutter. Because you're seeing the entire scene and deciding what stays in and what you want out of the picture. Which then affects when you shoot it, what you focus on, your DoF, your lighting, your angle, your shutter speed, and a range of other factors. It's less about "paying attention to the little things" and more about moving from "that's a cute picture, I'll take a snapshot" to instead "what story do I want this picture to tell and what tells that story and what distracts from it?"
As for light painting--that's a whole different subject. I do a lot of light painting and if I get started on that, you'll get "War and Peace--the Photo Text Version" from me. Best advice I can offer on that in one sentence is: be prepared to shoot a lot of exposures (each one a little different) so you learn what works and what doesn't.