I wonder if it's possible to come up with an alphabet where different sound clusters are addressed by individual letters. For instance:
'h𐑬se' and 'aut' - where 𐑬 is read as 'au' in RP, but as 'oy' in NI.
The downside is that the said alphabet would have more letters and it won't be always easy to guess the spelling based on pronunciation (still easier than currently in English), but the upside is that one can always read any word correctly in their accent.