Honestly, it's annoyingly monitor dependent :S As in I thought it looked fine, sent it to my missus and she complained it was too dark also. Then I actually saw it on her machine and...yah, too dark.
Now I'm kinda eyeballing it on my 4k Monitor + my laptop's monitor (which is also darker) to try and hit a mutual sweet spot, but ultimately I think there's probably no such thing and why plenty of games have gamma/brightness control sliders in their settings :(
With all that said, I think compositionally it is too dark/monotone and intend to add some fire torches. Either in the character's hand, or along the path/wall perhaps. Emission not actually emitting light means the fireflies don't exactly do what I was hoping either, but adding a crap ton of real-time point lights/shadows is gonna get expensive fast.
