It's a learning process and I think you've made some good progress, so don't worry about them not being perfect; "good enough" is fine. The "better rep" demonstrates pretty good positioning, IMO -- which is evident by the height you get on the bar: you could have caught that with no knee bend with room to spare. I think it's definitely time to start adding weight. I think you'll find that your form actually improves (e.g., you'll explode more, you'll be faster under the bar, you'll rack quicker, etc.) as the weight gets heavier. I find it impossible to perform a halfway decent looking power clean with anything less than 60kg.
Just a tip about fast elbows that helped me: think of your arms/elbows like whips. As you start to pull under for the catch, snap your arms just like you would a wet towel, and whip your elbows up. (Hopefully the analogy makes sense.)