For a trivial but high-visibility example, the very first two paragraphs of the document have "orphaned" words on the last line--a big typographical no-no. In

For a trivial but high-visibility example, the very first two paragraphs of the document have "orphaned" words on the last line--a big typographical no-no. In the first paragraph, the orphaned word is "of". If there's no way to squeeze those three characters ("of.") into the preceding lines then one should probably be a little more generous with the character spacing in the second line so that the "of." doesn't look so lonely. It is possible that as it happens there is no clean way to format that paragraph, or that Sile simply prioritizes other factors over orphan lines, but for a paragraph that opens with "SILE is a typesetting system. Its job is to produce beautiful printed documents.", leaving three characters orphaned on the final line is unfortunate. If nothing else I'd reword the paragraph to address this problem.