The five letters in red that aren't in use today, I was thinking that maybe you can also add the their pronunciation too, instead of having just a '-'?

I've added the names of those letters to the Georgian letter chart.

Oh btw, on the useful phrases in Bulgarian, it should be Воистину воскресе and not Воистина, a lot of people get that wrong, it's an archaic saying utilizing cases we've long dropped.

http://omniglot.com/language/phrases/bulgarian.php

Cool, maybe can add the pronunciation too:

ჱ [ɛi̯]/[ɛj]
ჲ [j]/[i̯]
ჳ [wi]
ჴ [qʰ]
ჵ [oi̯]/[oj]