]Silent and grave he wouldn't be.

As soon as I read Barbara's post, my first thought was that Col. Brandon's entire personality would have had to have been changed but still have had him be someone Marianne would have disapproved of... What would that Brandon have been like? Sir John has already usurped the part of the cheerful, playful man. :) Besides Col Brandon's mood is so interweaved into the plot, it's hard to imagine it being lifted out/changed without affecting the tone of the novel adversely. Another thing is, that while his character, as written, was done so that Marianne disapproves of him, it is also necessary to have him approve of Marianne which the first Eliza makes possible for him to do. Yes, and you're right, there would have been no second Eliza. I suppose he could have been provided with a guardian some other way but I think the emotional investment that comes inherent in the daughter of the one he loved and lost and in such a way adds depth and intensity to the relationship, not just a duty or responsibility.