Thank you both for the feedback!
Gustav- I'm honored by the comparison to Whitacre, and I understand what you mean as far as awkward movement in the voices and chromaticism. I haven't formally studied the types of harmonies that I used throughout the piece, and my judgement of my own work isn't too reliable, so of course the ear of another musician is very helpful in figuring out what does and doesn't work. If I do record the piece with my own voice (although I'm not so sure of my soprano chops haha) I'll post a link as an addendum in this topic.
pateceramics- Yes, the sound sample is the MIDI choir soundfont built into Windows. I admit it doesn't sound very good, but in the future I'll be looking into more professional programs and sample libraries to better represent the sounds I hear in my head. Your insight about the technicalities of choir are very helpful :) I didn't consider the relative balance of parts in a typical section when writing this, so knowing what to expect if I tried to arrange a performance is definitely good to know.
Again, thank you both; I'll try and apply some of the ideas you all wrote about in my next effort for choir and post it here.