When I wrote "This is all about LR's personal dislike of CW" I should have chosen my words better, and omitted the word "all". You make a good point that LR sees CW's seemingly reckless and impetuous character as adding to the risks associated with his career. But I have the impression that she also finds these characteristics personally distasteful. I think that is definitely true about his wit, which has no bearing on the riskiness of his career but which Lady Russell has no taste for.

The comparison with Mrs Gardiner and Elizabeth is interesting. I see a difference in that Mrs G is warning about the financial imprudence of a match with a man whom she personally agreeable. By my reading Lady R's advice, while driven by entirely reasonable prudential considerations, is also biased and tainted by her regard for rank and by her personal dislike and distrust of CW.

That is what I find manipulative. I think she is taking unfair advantage of her influence over Anne to push her own agenda (a marriage to a man with wealth and status who's personality suits LR's notions of what is agreeable). I do not think Lady Russell is doing this for selfish reasons - I'm sure her motives are entirely benevolent. But I think she is too absolute in her opposition and somewhat manipulative in her way of attaining her aims.