Here are a few thoughts.
On the hearing aids, consider giving them another try with the volume turned down a little or a lot. This will likely reduce the harsh sound. Over time, if you want, you can always turn it up. You can also find out if your model offers a music program and then have your audiologist add that. Again, use it with the volume turned down. The main reason to get used to the hearing aids is to change how your brain responds to sound in the coming years. The tinnitus is from your brain not receiving the sound signals it used to from your ears. The hearing aids might slow or stop that getting worse over time.
On the system, considering your list of speaker candidates and goal of maybe moving things into your home theater, I'd stick with brands that have really good center channels. For simplicity, I'd forget the sub and then use as much of your budget on speakers as possible if you have room for floor standing models.
Here's an example of what that could look like.
speakers: Ascend ELX tower (titanium dome) or Arendal 1723
amp: Buckeye Hypex NC502MP
source: Wiim Pro Plus or Ultra (RCA to XLR cables to amp), note that the Ultra doesn't have Airplay2
Rationale: this is a simple system to setup and use and just enjoy however you want. The WiiM offers easy EQ so you can get a pair of good speakers and tailor the sound to your preferences. The amp has tons of clean power. This approach is more flexible than looking at a bunch of speakers to get a certain sound. It also lets you change things over time. If you want the option to listen with or without your hearing aids, you can even make 2 EQ presets for each scenario.
The amp and speakers are excellent and the WiiM is the cheapest part so as technology changes, you can swap it out. The DAC quality is excellent and there's no need to add a separate one (not so true of the WiiM Pro compared to the Pro Plus).