OK, I'm going to suggest that your version did not improve on the version that made you "LOL."
Why did English scholars use all those "thees" and "thous" instead of just "you?" Well, partly to maintain pronoun distinctions in English that existed in the original language. While "you" in modern English is pretty much the all purpose second person form of address, it wasn't always so. English (like a lot of languages even today) had a second person plural pronoun ("ye") and a second person singular ("thou"). When translating languages that had fine pronoun distinctions of that sort, it made sense to render them as closely as possible in English, even if that involved using slightly archaic forms of address. Also, the use of "thee" and "thou" often connoted an intimate, familiar relationship between the speaker and the person being addressed, which would often be reflected in the original texts if the speaker was addressing deity (or, purportedly, if deity was addressing the speaker).
Now, many modern languages still maintain a familiar form of address, even though they've fallen by the wayside in English (and an argument could be made that English is not richer for having lost them). If you read the Isaiah passage you quoted in modern French, for example, the familiar second person pronouns would be used. Many modern languages, despite having a less expansive vocabulary than English, still have tenses and forms of address that allow the expression of certain kinds of feeling and relationships that are hard to render in modern English, but can still be communicated if you use an older (but as attested by your "translation," still quite intelligible) form of the language.
As to it being "harder to build a cult around prose," well, maybe. A lot of Isaiah was poetry, not prose. Poetry is much more difficult to translate into a foreign language (ancient Hebrew to English, for example), so a lot of the versification gets lost. I'm sure the translators did their best. I'd still maintain, in light of what I note above, that their efforts are probably superior to yours.
If your goal was to point out that a translator can make most any text less compelling by ignoring any depth in the original expression and brutalizing it down to a few words conveying a basic idea, then I think you are correct. But I'm not sure that language or communication will be much improved by the exercise.