My biggest issue with N4106 is that COMBINING LIGHT CENTRALIZATION STROKE BELOW and COMBINING STRONG CENTRALIZATION STROKE BELOW are given combining class 220 (below). The only reason this was done was so they could be used with the proposed COMBINING PARENTHESIS BELOW—that's it. N4106 even asks that a paragraph be added to the standard saying that these characters are typically rendered below left, not below. Isn't that one reason why we have different combining classes? Why not make them combining class 218 (below_left), and add a COMBINING PARENTHESIS BELOW LEFT character? Sure, it means one more character, but now there's no extra explanation needed and no extra rendering requirements for COMBINING LIGHT CENTRALIZATION STROKE BELOW and COMBINING STRONG CENTRALIZATION STROKE BELOW.
Also, I think the combining class for COMBINING PARENTHESIS OVERLAY would be 1 (overlay). But that's just me. Two editorial problems: I. U+AB53 still has an annotation pointing to the removed U+A7AF LATIN SMALL LETTER CHI; II. the glyphs for U+AB5D and U+AB5E don't match their names. N4107 has the same problems, including the spelling "Volapük." —Ben Scarborough
