[mkl]

I learned Shavian a few years ago, with my own transliteration dictionary based on my New Zealand English pronunciation (which Shavian doesn't quite seem to handle all of). Unfortunately, different dialects of English have very (inconsistently) different pronunciations, and hence there would be many different spellings for the same words; I really struggled to read Shavian written by people from other parts of the world. Going phonetic may well mean giving up on fast reading through whole word recognition.

[idle_zealot]

Or it would require standardizing on certain pronunciations.

[mkl]

I don't think that's possible. Much of the popular media in the English-speaking world is in a standard-ish General American accent, and yet still the diversity in accents is enormous.

The only way I can think of to do it is if all phones and computers had really good voice control systems that nonetheless only understood the standard pronunciation (like early versions of Dragon dictation). The voice system makers have a vested interest in not doing that, but in understanding everyone as they talk. Arabic has tried for centuries, with the full force of a major religion, and yet still the language is splintered into mutually unintelligible dialects.

People talk how they talk, and it's constantly changing. I don't think anyone can control that.

[cezart]

My native language, Romanian, is written exactly as it is heard. Dialects with differing pronunciations still exist. In practice, everyone who speaks in dialect, writes the words as if transliterated from the official pronunciations (which is taught in schools), but pronounces the words as they're used. So in writing everyone gets each other. Orally, it can be a bit difficult sometimes.

[idle_zealot]

This is what I meant to suggest. Pick a canonical set of pronunciations to be used in writing.