Hard to tell from the very short context, but the “and ‘d” looks like it’s an elision for “and I’d”, so I would think the ‘d should stay separate. Kind of link ’n, etc.
As I discovered this weekend, we have a lot of ligatures in the corpus that shouldn’t be there, according to SEMoS. A LOT. :) We don’t (or aren’t supposed to) keep Latin ligatures, to the best of my understanding.
The three phrases non-English phrases should definitely be italicized/semanticated (and the ligatures removed).
We generally leave British spelling alone, and we have a number of “syren”s in the corpus, so I would think it should stay. If Alex decides to change it, it will have to be changed corpus-wide.
Re the letter, there’s been some brief discussion on the list in the past about blockquotes like that, i.e. with an intro of some sort that’s not actually part of the quote. I personally make them blockquotes, but I don’t know that everyone does. However, in this case, since it’s a letter, and everything, including the signature, is formatted as a letter, then IMO it should be in a blockquote. Which also means that the various pieces should be semanticated, i.e. the salutation, valediction, and signature, and the signature should be in a footer.