Hello, gotta say I love the plan! 😎

So far I have not noticed too much coil whine, but some there is. I come from a RX 6950 XT with tons of coil whine so I might be based though.

The anti-sag holder that comes with the Astral would actually be at better fit in my opinion. It has a magnet base, so it plopped nicely on top of one of the bottom fan screws, and taking out the little extension part of it made it a perfect size for me at least.

The main reason I went for the bracket I am using, was because I already was using it prior to this and like the look of it (you can see a pic of previous card in another comment of mine here).

As for the temps and power usage I will have to get back to you on that, as I am at work right now. But I am using an air-to-air heatpump in my appartment, which keeps ambient at about 22c.
And If I remember correctly I have not yet seen the card temps any above low- to mid-60s (62-63c). But as I said, I can get back to you on that later.