Hi! I agree that it works well in terms of harmony, form, etc. Bonus points for achieving such interesting harmonies with almost no divisi and relatively singable voice-leading (just a couple awkward leaps in there that might be asking for trouble, but mostly good). The harmony seemed to lose a little focus at the end (maybe that was deliberate?) but apart from that, the harmony flowed well and created a nice form.
The main thing that bothered me was how the words flow (or don't flow) with the music. If you sing through every part (which, simple as it is, is the best advice I ever got about writing for choir--you don't even have to be a good singer!), are there spots where the melody doesn't really match the emphasis and inflections of the words? There are a few moments where the word stress seemed unnatural to me ("let THE earth" in the tenors; "na-TU-ral-ly", "pla-NET", etc.)
I tend to agree with aMusicComposer about the bass low Es. Since you'll generally have the baritones as well as basses on that part, it's a good rule of thumb to add an upper divisi part whenever you go below a G or so. While (in theory) it's true that a good choir tunes to the basses, they'd only be able to fudge the tuning a small fraction of a semitone without throwing the whole progression off, and sometimes (like at the beginning, where the sopranos are already holding an E when the basses come in) that's not even an option.
Lastly, if you do manage to get this in front of singers, I hope you follow Pateceramics's advice on text notation in your original post of this piece. It will make the words, and the way they line up with the notes, much easier and faster for them to read, and they won't waste time trying to figure out what you meant by "a-nd", "spro-ut", etc. 🙂