Nice piece, Hogan, like the tone.
Watership Down is one of my all time favourites, I read the novel nearly every year as I grew up and really enjoyed the film. You're right, the CGI reboot didn't work, but if you want dark, the series (made 1999-2001 by the same team as the animated film) gets really traumatic and veers toward the demonic (I haven't completed a full viewing of that, yet!) and never-never consider watching The Plague Dogs (1982) - I haven't emotionally recovered form that one!
I have written in-depth reviews of a few on your list here on Medium, including both versions of Watership Down - you can find my thoughts on the good version and on E.T. in my list of 'Favourite Five-star Films'
https://remydean.medium.com/list/favourite-fivestar-films-d16f5fde80ad