This is a fun tune, Lyndon. As a song leader, I believe I’d find v1 easier, since the measures follow the musical pattern more closely. I like that it shifts keys and timings, as though it’s traveling through a musical landscape. But of course that will make it harder to learn.
In the case of the unison, I agree that something feels a little odd. Starting out in unison, or going back to parts on “names” would feel a little more balanced to me. But that could be just me.
I would guess that singers will find measures 5 and 6 a challenge, but not too hard. The last line will likely be harder. Sopranos may need to be able to hear the fa-te leap before they can sing it, and the re-do-la-sol-re-sol will probably be the toughest for them to get. I find it a bit unintuitive, though I really like how it opens up into the tonic at the end without any soprano movement. Love it!
The other parts won’t have nearly as much challenge throughout the song, and will probably enjoy their parts without being overwhelmed. A good congregation should be able to get this with some practice.