Same as a Chimera Linux user I'd definitely recommend trying it. I was a Void user beforee and was Swithering whether to go full BSD when I stumbled across Chimera which gives me the best of both worlds.
I was a serious Arch user for 10+ years when I finally decided to give Void a go on an old laptop. Needless to say Iloved it so much that it is now my daily driver.
I even had a blip for a month where I thought I missed Arch but nope I just came running back home to Void.
Give it a try you won't be disappointed also take a read of this blog Unmasking the hidden gems of Void Linux
To get neofetch to display river and not sway make sure that you have either lsof or fuser packages installed and it should display river then.
See lines 1902-1903 from this link.
Thank you and tbh I haven't attempted to run hyprland on void as I used to run it on arch as my daily. Since switching to void I haven't really looked back and don't feel the need for all the bells and whistles.
You could use swayidle and add a line to use either light or brightnessctl to dim and restore the brightness. Or just as I do turn off display after a certain time. This link should give you an idea.
https://wiki.archlinux.org/title/Sway#Idle
Maybe try wib here and use a rule in your Sway config to toggle it ?