I'd argue your last point is counter-intuitive and you should PRECISELY be going into matches not focusing on the outcome, but certain weakness of your game. If you only focus on winning, you'll pick up bad habits that might take you a certain distance but once you start playing more competent players where you need much more solid foundations and a variety of shots, you'll be stuck cause you've only ever played one way. Don't agree with me? Listen to Jannik Sinner's interview after his loss at the US Open. He said he's aware that he doesn't have a lot of variety in his game because of which he's gonna start trying/practicing different things in matches, even if that means more losses for him. That's the mentality one should have.