I'm in the process of planning out a new type family and I'd like it to cover as much of the Latin, Greek, and Cyrillic scripts as is practical (i.e. in modern use - I'm not too worried about ancient or archaic languages). Looking through the Unicode Standard, I realize just how little I really know about the Latin script alone! So I'm trying to sort through the various code charts to figure out which characters I need.
I already know to include all the characters in Basic Latin, Latin-1 Supplement, and Latin Extended-A. I know the basic diacritics, punctuation, "letterlike symbols," etc. I can identify the basic necessities for the Greek and Cyrillic scripts. But beyond that I'm lost. The following is a list of Unicode pages I'm interested in. Any advice on which to include and which to ignore would be great.
Latin Extended-B, -C, -D, & Additional
Spacing Modifier Letters (besides the basic diacritics)
Combining Diacritical Marks (besides the basics)
Greek and Coptic (beyond the basic alphabet)
Phonetic Extensions & Supplement
Comb. Diacritics Supp.
General Punctuation, Supp. Punctuation
Superscripts and Subscripts
Cyrillic Ext.-A & -B