Just two of you guys, today, but two of my superstar students!!!
Look at you, just bulldozing through your new book, and you just started it!! Keeping high wrists, playing on fingertips as you articulate, and engaging your core muscles instead of raising your shoulders has improved considerably, but you have a ways to go yet, so keep it up!! Your dynamic variation as you play and sense of shaping the phrase has also improved.
Remember, your tummy/core muscles should ALWAYS be engaged (quite intensely) to one extent or another as you play. Doing so not only coordinates your playing apparatus, but it focuses your concentration!! Try it in other areas of your life – while playing sports/doing gym exercises, and while writing a test/trying to remember the answer to a question. It works!!!