Hooray, Bella! Lucius doesn't like her, either - first and foremost because she doesn't like him, and naturally that's indicative of a fatal character flaw. Also, she's a Death Eater, she's too forward and aggressive, she doesn't seem to want a family and she's a woman, and ... that is all so utterly distasteful he finds it hard to believe she's related to Narcissa. Well, he used to. Now that he can see the Black streak in his own wife, the picture is coming into focus a little. But, yes. Bad in-laws.
Xavier sounds like just the sort of man Lucius would want to ingratiate himself with. He can expect bribes, flattery and expensive liquor. :) They should have a chat. (Or a smoke.) Narcissa is, I think, going to be pressuring Lucius to start involving himself with the Ministy in ways above and beyond paying people off, so he might make a fun connection.