Oscar Ogg, in his book "The 26 Letters," show how our letter 'A' came from the Roman which came from the Greek alpha which came from the Phoenecian aleph.
An aleph is a point which contains or reflects the entire universe, or a microcosm which echoes its containing macrocosm.
Borges has a story about it.
In blackletter, the a seems to me to capture the soul of the script. While the i contains all (both) the necessary strokes and the o contains the spacing and core structure, the a, with its characteristic tail and its cocky central stroke (I add that for distinction, but it is an historical mark) kicks the alphabet off with what Frank Zappa called "eyebrows."