@Sattut, I think that you are going outside your area of expertise - or at least speaking too broadly- when you say that " US humanities majors will generally have taken some courses in more “practical” areas". Which humanities do you mean? English? History? Classics? If so, you are mistaken about (most) US programs. If you mean Law, you are partially correct, but only because of the different course structures.
Moreover, the world rankings do not agree with your opinion that ‘humanities’ in the UK and Europe are generally better than in the US:
8 of the top 10, 15 of the top 25, 44 of the top 100 globally are US, including not just elite private colleges but state universities such as Texas (Austin), Virginia, Wisconsin (Madison), Ohio State, California (UCLA, Berkely, Santa Barbara and Irvine) and so on.
Similarly:
again, 8 of the top 10, 15 of the top 25.
Also, I disagree with you that “Americans are at a disadvantage applying to UK Universities, because they haven’t concentrated on 3 subjects and preparing for exams”. In fact Americans have a straight run at UK universities for all but the tippy top universities. Imo the challenge is not getting in, but managing it once they get there: there is much less hand-holding, the emphasis on exams requires more self-discipline than more continuous assessment, etc.