Unicode Support for Extended Character Sets

I am interested in studying whether a specialized font for dyslexia can help my students who are studying phonetics better identify the phonetic glyphs. Having downloaded the font and attempting to utilize some of the characters, glyphs from the Phonetic scripts do not present in anything like the rest of the OpenDyslexic characters used in English orthographics. Some Examples are these variations of characters:
/a, ɑ, ɒ, i, ɪ, u, ʊ, z, ʒ, s, ʃ/ Also, as diacritic placement is important, how does well does OpenDyslexic handle the placement of diacritics with individual glyphs? Some Examplesː
/ aʊ̆ɚ̯, a̽ɨ̠ /

If the font assisted in comprehension, I know many academics who would be interested in utilizing it.  I would actually be willing to help with development of the font to include those characters.  I've never used glyphsapp, but I'm fairly adept with technology and willing to learn.  Would someone give me a bit of help to jumpstart that?