What would also be awesome is to get rid of the leve timer and instead make it so the counter in the Adventurer's Guild is only openned between specific hours. Make it so we can get unlimited leves but you have to be on during let's say 10:00 ~ 18:00 is when the guild leve counter is openned. Certain leves could also be only completable during a time frame. So like fighting bats or undead would be "Night Leve"s. This could add a whole new level of depth to the game having Day Leves and Night Leves Day Leves being between 07:00 ~ 18:00 and night leves from 18:00 ~ 07:00. This would be more immerssive and would also probably make soloers and RPers happier that having a clock that deals with real time, ingame clock adjustments would have to be done but I think it would be for the best. If I recall FFXI had a system like this for the crafting guilds and certain shops.
I like the idea that it should be much darker at night and in caves, a cool thing would be for an actual Torch useable item to be created or Torch Sub Hand item (Glowing Weapons, Fire Sword, Lantern Shield?) which could make it so you have better visability at night. Some nights could be darker than others to add some variance and make it so that having a torch item during those periods is very useful. (Cloudy weather at night could make it darker?) This could also lead to new Conjurer or Thuamaturge or even Arcanist spells for lighting of a path, visability buffs and such.
Also, having Diurnal, Crepescular, and Nocturnal behavior in certain mobs or species of mobs would also ad some depth. Having Moles being only in caves during the day but then spawn out on the open fields at night. Fewer Marmots out on the fields during the day and more at night. More Plantoids during the day. More Insects during the night.
By Clock Adjustments I mean that they should make the clock a little slower, not match it to real life but simply make it slower so that the day and night cycles are a little longer.