Hey! Been enjoying reading your devlog. Liking your maps, so many RPG Maker games had square, inorganic feeling maps, but yours do a lot more to feel natural!
I'm a bit late to the party here, and it's been a long time since I used RPG Maker, but I remember there was a way to "tint" the game rather than have to recreate the whole map. I used to do an event with no picture in the corner of the map with Switch: IsNight ON, and then include the action that set the screen tint to a dark blue sort of colour. If Switch: isNight OFF then the tint is set to normal/none instead. I vaguely remember using this to simulate early morning (orange), day (none) and night (dark blue) based on Switches or possibly other variables. You can also use this switch in events so that they only are triggered during the day or night. That way you don't have to create multiple tilesets and events!