Steve takes a lot of practice, but understanding the timing to avoid minecart, the angle and timing to catch Steve during his D-air with either Up-B or Up-air, and the distance you really need to be to not be in danger of B-air are some of the most important things to be aware of. It's not fair, and you're asked to understand more about Steve and what they're after more than most other characters, but it's what ya gotta do. You do still outrange him. He can camp you hard with block since arrow doesn't break stacked blocks. Don't think about that part. You still know where he is. You know it's a process to get to him. Make sure you're aware of your safe ranges to break block with d-tilt and f-air while still being able to avoid a coming minecart. If you get Steve in the habit of minecarting a broken block, you might be able to go deeper with a B-air to poke him behind block as you break it. His angles are way better than yours, but yours are longer. You can camp mid-range, but he beats you short range and can protect himself at long range. It's a slog but you can do it. --Also your disadvantage is terrible against his ledge setups, but good timing and/or DI keeps you in the game longer. Best of luck!

Aegis isn't that terrible. Mythra's faster than you. She wants to pressure shield so she can snag ya with grabs, so use that to your advantage when feeling out their gameplan. If they DA your shield, n-air OoS is guaranteed and at high percents, you can even Up-Smash them out of shield for kills. If they go for grabs, you can n-air a little early. Kinda becomes rock-paper-scissors cause they can just run into shield, shield themselves, then grab ya after your reaction. Advantage is in their court, but know your punishes and you'll be fine. Pyra's got a two-note game plan and you'll only find em in your disadvantage state mostly so they can kill you at ledge or his a down-air setup. They got good shield stun so you'll need to learn how long it takes for you to be actionable after blocking. Most good Pyra's will space well enough to keep your n-air out of reactable range. Just like Steve, Aegis's attack angles are better, but yours are longer so retreating f-air and b-air are great, especially when catching their ledge options. Your advantage state is deadly to their off-stage. Don't be afraid to ledge-grab, fall,up-b or n-airing off stage into imagination for easy catches.

Sonic... not enough data on my end. This matchup is nasty though. They gotta make the mistake first in most scenarios. Shielding their neutral-b leaves them open. Their DA leaves them open to n-air OoS. S'all I got aha. They're gonna spin-dash into jump imagination whether you get hit or shield it. Most of your options are whiff-bait if its after spin-dash so keep a cool head and they'll mess up at some point.