I agree with most all the comments posted here. They are all well-founded, even though they differ some. My violinist partner Ron Erickson consults with me on harp notation, and he also gets advice from other experienced orchestra and solo harpists for his editions of ensemble music. We all differ to some extent on a standard approach, but he has concluded that an editor should follow a consistent standard and vary it only ad hoc to improve readability. He stays with Salzedo’s direction to place left pedal marks under the right pedals. A serif font is more readable than sans-serif. He places the marks between the staves to help those with less-than-optimal eyesight, but size depends on how much space there is. A crowded page is no fun. The biggest question is where to place them in relation to the notes. Always somewhat before the note, unless that note is a change of accidental. Harpists need to be notation-literate with the rest of the musical world, rather than “re-invent the wheel,” as Carl says.