Never going to get tired of your feedback Yo! Specially when you put some real life examplesyo wrote:Rodrigo,
I love the frequency with which you are posting. It does take a lot of time to improve, but it is an investment that pays off exponentially! I still have a long way to improve as well, but the benefits I have seen from investing the time are amazing. The best part is to not think about sketching technique as much when you are working on a real project, you can focus your attention on your ideas and not as much on line weight and perspective because that becomes second nature. The second big pay off is speed. There are many times when I get clients who have a rush, sometimes they need something in 48 hours. Or sometimes 3 clients call the same day and all of a sudden you are swamped. Being well practiced alleviates some of the stress associated with that, and gives you the confidence to deliver.
Keep working on it! I'm seeing big gains for you already. And remember, it isn't a strictly linear progression. You will have days where everything is going great, then a setback. It's ok, just keep plowing forward.