Spoiler: sadly not true. EO 10834 (called out in 4 USC SS5) specifies placement and proportions and colors of all elements.

https://upload.wikimedia.org/wikipedia/commons/7/7d/US_Flag_spec_TIOH_5-1-17_1967.jpg

If you're willing to hit up Ebay for "new in box" options, you can get some pretty good stuff under $180. For wireless:

Fairbuds XL: Made by the Fairphone folks, who have a very good reputation for repairability and longevity.

Sonos Ace: Stainless steel pivots, replaceable earpads, huge battery, no glitchy touch controls. Mine have treated me well so far. Absurd you can find them this cheap, considering the original MSRP.

• Curves: Curves take a lot of time, because fat redistribution is a slow process. I've been told it kicks in after several years. Excercise helps, and I think it's mostly because it improves your metabolism. Despite what some have said, cycles of (unintentional) weight loss and gain absolutely did not accelerate redistribution for me.
• Diet: Honestly, just eat what's healthy. Hydrate. Get good quality sleep. You're a growing young woman, and they don't call it "second puberty" for nothing.
• Breast Growth: Congrats on the cup size! But I can't say if it's slow or fast. The spectrum of "normal" breast growth is wide and nonlinear (growth spurts). If your nipples hurt, then it's working, so celebrate and treat yourself to ibuprofen and a hot pack.
• Fem Appearance: Get hair advice from a trans-inclusive hairdresser. Good conditioner made more difference than I thought. Painting my nails is a special euphoria for me; even when I feel like a ceramic construction material, I can look down and see pretty colors on my hands. Try on lots of clothes, including stuff outside your comfort zone.
• Mannerisms: Fem-coded mannerisms are a wildly deep topic. I'd suggest looking at photoshoots to see what they're doing with their hands, how they touch their faces, and how they carry themselves. Important: try to only look at photoshoots of people whose bodies remind you of yourself, and remember that magazines are designed to trigger self-loathing spirals in their readers.
• General Advice: "Try everything and keep doing whatever felt good" seems to be a winning strategy. You have a new body, new hormones, and a new outlook on life. Who knows what kind of person you could be. Discover yourself!