What are opinions on how to set different letters in drop caps? I know it depends on the font, but setting aside unpredictable ornate initials, what are the accepted guidelines for, say, standard simple initials opening a book chapter or other long text document? I'm primarily interested in the guidelines for relatively formal straightforward documents (books, business reports, etc.); obviously people can do lots of whimsical things in informal or more ornate situations.
In particular, I'm wondering about two issues:
(1) Obviously the first line should generally be brought in closer to the initial. But assuming the initial occupies three or more lines of text, when is it (if ever) a good idea to pull in the second and/or subsequent lines to follow the shape of the initial? I've seen this done with A, V, and W to create a reasonable effect with the lines flowing along the diagonal. But I've also seen lines pulled in with other letters that might produce excessive whitespace otherwise near the bottom (T, P, F) -- once even in a middle line next to an E, which looked quite strange to me. Oh, and L is obviously its own problem with more than two lines. On the other hand, I've often seen initials without such manipulations, which can sometimes leave a lot of whitespace, though they look a little more "formal" to my eye.
(2) I know this is largely up to the eye of a designer and the specific font, but what are the general guidelines for aligning the left side of the initial? I know that round letters (C, O, Q) look better pushed out slightly into the margin, and perhaps those that slant up on the left side (V, W, Y) or have an uneven left side (J, T). With pointy serifs, it seems like it might even be a good idea to nudge out things like an I a bit. But how far is enough (or not enough), and how far is too much? Are there general guidelines for such things?
I don't expect that there's a magic equation or formula for these issues, which are highly dependent on the individual circumstances. But are there general opinions or rules that people follow beyond what I've already mentioned here?