Came across this interesting realisation about the arrangements of the Baaraakhadi in Devanaagari.
This is about how you use your tongue and mouth cavity to articulate a particular sound.
There is a sort of logical grouping and progression about the arrangements.
क, ख, ग, घ, and ङ sounds are all articulated by the tounge against the back of the ceiling of the mouth cavity
For च, छ, ज, झ, and ञ sounds, we move forward and use tounge against the centre of the mouth cavity's ceiling
ट, ठ, ड, ढ, and ण are produced more forward behind the gums of incisors
त, थ, द, ध, and न are produced with the tounge against the teeth
and प, फ, ब, भ, and म are produced by the lips alone.
Considering the expertise on grammar that stands 2.5 millenia, this phonetic formalism is not a surprise.