Good going there Aidan, the last image is actually a good improvement, in a few ways too,
1st the noise is less, especially being a larger file dimension size, noise still shows up less
2nd, you have rid the image of them 2 or is that 3 donut dark rings, one left center, other low left with one half next to it ?
3rd, the stars are smoother - without rings in them..
Over all, a rather good jump forward in many ways, well done , maybe some loss of signal in the fainter extensions, but in reality, one can't just get all factors of processing at once, that is this hobby's challenges
All the best & kind Rgrds !