How about a penalty of 20 to Big Guns and Small Guns, 15 to Energy (since PER is already impacting it) and 10 to Melee (even though melee is close quarters, it's still harder to fight in the dark than in day). And again, NPCs wearing power armour don't get the penalties.
Eventually you may want to attach a warning to the next release, until the subject has been play tested a bit?
I do not understand the mechanics of decreased skills sufficiently, but I know that, given above values, most of Big Town's residents fight with a small arms skill of 0 (or -5, if negative skill values are possible), at night.
Just wondering if some players may feel uneasy about this.
(Or do these skill changes not affect
non-MMM-NPCs?)
A lil' rant (targeted at Bethesda, not Mart) :
Apparently, Bethesda must have planned on all minor settlements to die out, later in the game (or is it a bug that deathclaws tend to spawn right inside the settlements?). What they may not have planned on is that some players take offense in the technical inability to prevent that from happening.
(E.g. either teach Big Town self-defense
or repair the robots (Why not both?); you can repair robots, but only in this one quest and
never again (wth?!); you can practically own the wasteland (I have enough resources in-game to buy it) but you cannot do anything to help the small settlements (aside of the town specific quests, which do nothing to help against deathclaws).