There is also no need of double conconants such as: dd, tt, ll, rr, ss and so on. With the exception of g: for instance English can be pronounced with or without the 'g' sound. (either a nasal 'e' sound followed by an 'n', or the nasal 'e' sound followed by an 'ng') So with the new spelling English can be spelled either: Ínglix or Íngglix, depending on how you pronounce the word.
First off, I don't think an orthography that can change depending on how someone pronounces a word is a bad idea. There would be too much deviation in spelling after a while, I personally think that it would be too confusing. Some double letters would be important for example moose and mousse would look and sound the same. You also loose the distinction between in and inn and to and too (and two).
ai- always pronounced like 'i' in spine.
ei- always pronounced like 'i' in spike or like
I'm pretty sure there isn't any variety in the way those i's are pronounced both being /aɪ/.
Two more questions, first what about the digraph er by some it is pronounced /ɚ/ and by others /ə/. In your alphabet raitѳ raitɛ reitѳ reitɛ all sound like writer. (And the way I pronounce words, rider also.) Also what is your solution for wh being pronounced as by most as /w/ but by some as /ʍ/?
Also đeɛ (đeѳ) would be how you write there, their, and they're. Problems could arise in statements such as their dogs and they're dogs looking the same. You also loose the contraction of the last one đé ár changing into đeɛ. (And I believe in non-rhotic it would be đé á into đeѳ).
I apologize if any of my points are invalid my mind is foggy at the moment. One point I couldn't figure out how to explain is how non-rhotic accents extend vowels in words such as hard and car and if this could be a problem since there is no way to show this extension.