Still reading through. Twilight Domain is fantastic. Perhaps too good. Great spells, heavy armor and martial weapons, and nice features. I feel it may be a bit above the other cleric domains, and is probably well above for a 1 level dip via multiclassing. But not enough to be broken, just very good.
Hey, question about their CD. It says the area is filled with Dim light. The way I'm reading that is thematically - it's dim light in there baring other magic, regardless if it's bright light or darkness elsewhere. In other words it brightens darkness and dims bright light. Which is very on-point for a Twilight domain. Is that your read as well?