Glyph selection:

As part of the brief, we must submit a full 26 letter alphabet and also 6 additional glyphs which must have reasoning behind the choice. 

@ I will use the At symbol which has become popular due to the use in facebook and also email to contact friends. Tom seems like a very sociable and friendly person, so I feel this glyph will represent him well.
! Looking back at Tom's handwriting, he writes very boldly and blocky, as if every sentence requires an exclamation mark at the end. I feel that is quite fitting.
< The less than symbol could represent a shark biting which Tom revealed to be one of his greatest fears.
. The full stop is a vital component in literacy, so I feel that is vital to the alphabet.
, Commas are also vital to the alphabet so they are necessary.
- The hyphen of negative sign can be used vastly in writing, and it could also represent the things that Tom wants to cut out of his life.