A great start, PDB. I have yet to do my own laserdisc capture to compare with (I have the 1992 collector's edition here, which should serve well enough) but here are a few preliminary observations (based on more scrutiny of the book's frame blowups):

Planet exteriors: if anything, the 'new' colouring seems more accurate - judging from the book, this stuff was shot with a very cool blue filter (towards turquoise). I wouldn't change those.

Ash's bubble: should be very neutral: not blue, but not purple either. Just dial it back until the grey panels lose all the blue colouration.

Ripley: I can see why this shot was so problematic! The trick will be to take out the teal and rosy up the skin tones without giving the whole shot a pink/purple cast. The shadows (particularly her hair) should remain black, rather than reddish-black. Hopefully there aren't too many challenging shots like this.

Dallas and Lambert in the airlock, Ash in the airlock bay: look terrific. Perhaps just look at that Ash profile again, which is way too hot at the moment.

Of course my reference has its own limitations, so you should judge what you're happiest with. But good progress overall!