Even pay and fay
You do realize that Pay and Fay are really the same letter, right?
in Hebrew, whatever letter you see is what it is and always will be, it doesn’t change
I know that in some circles it is fashionable to pronounce a cholom as “oy,” but in others, a cholom without a yud after it is “oh” and with a yud after it is “oy.” Likewise, a shuruk can have a different sound depending on whether or not a yud follows it.
based on the next letter
Usually not, but often on the preceding letter (such as the rules surrounding when a dagesh is used, or whether a sheva is a nah or nach).
Ultimately, I think your original premise is flawed. You are comparing two languages (Hebrew and English), concluding that Hebrew is easier to read (which may or may not be true) and then concluding that Hebrew must be easier to read than ALL languages. Needless to say, your conclusion is not supported by the premises of your argument.
The Wolf