Address comments by 96187 ...

... whose local knowledge of how characters are actually used identified
more appropriate characters to map to.

soft hyphen -> nothing (since it is invisible)
multiplication -> x rather than * (visually closer)
remove duplicate oe
Address various comments by Philipp Wolfer ...

... based on actual knowledge of how characters are used in practice.

low quotation mark -> normal quotation mark rather than comma
oi should be gha -> gh rather than oi
ideographic punctuation, multiplication / division and middle dot are not punctuation