Unhallow says in part, emphasis mine:
you may choose to fix a single spell effect to the unhallowed site. The spell effect lasts for 1 year and functions throughout the entire site, regardless of its normal duration and area or effect. You may designate whether the effect applies to all creatures, creatures that share your faith or alignment, or creatures that adhere to another faith or alignment. At the end of the year, the chosen effect lapses, but it can be renewed or replaced simply by casting unhallow again. Spell effects that may be tied to an unhallowed site include aid, bane, bless, cause fear, darkness, daylight, death ward, deeper darkness, detect magic, detect good, dimensional anchor, discern lies, dispel magic, endure elements, freedom of movement, invisibility purge, protection from energy, remove fear, resist energy, silence, tongues, and zone of truth.
What does the bolded section mean in the context of Deeper Darkness? If I choose to exclude e. g. Evil creatures, can they see through the darkness, since RAW the effect does not apply to them? Additionally, most of the other effects on the list (e. g. Bless/Bane) target creatures, whereas Deeper Darkness targets objects, so what is the object? The point listed as the target for the Unhallow?
Unhallow: Range touch, Area 40-ft. radius emanating from the touched point
Edit: Upon reflection, it seems like Silence would have a similar issue, since it's also an area that's centered on an object.