Since we as Guardians as suppose to be fighting the darkness and as it stands right now we are on the losing side of that battle it would make good sense that the darkness should be more prevalent, the player should feel like they are caught up in something that is overwhelming them. I like the idea of having more enemies at night or higher level ones but I can see that this could cause issues for new and low level players. So how about we be allowed to select an alternative patrol option with a modifier like 'Guardian's Light' with this modifier whenever night comes (or all the time if you really want to push the whole universe consumed by darkness idea) the player receives a debuff of 10% to 20% to all damage they deal whilst the enemy get a 10% to 20% buff to all damage they deal. This is essentially the same modifier that is applied when low level players face higher level enemies, but would be active in this mode regardless of the enemies level. Given how this game works mechanically this modifier would also end up stacking with that of the level difference damage modifier meaning higher level enemies would probably one shot you. Regardless of whether this is a good idea or not I think the darkness needs to be used more in the game rather than just in darkness zones for restricting respawns and activating mission specific modifiers (even though yes technically that's what my suggestion is). EDIT: I forgot the modifier would also offer a 5% to 10% increase to xp earned for kills (kills only) because the guardian is successfully pushing back against the darkness with each one.