NES style game in Unity - Part 4 - Getting in shape!

Looks like an NES game, but it's made in Unity.
The character sprite is a modified sprite from Konami's Castlevania III - Dracula's Curse.

Progressing slowly but surely! I am getting more and more satisfied with the look of the game. It definitely looks like something from the NES era. Same resolution, same colour limitation. Same feel!

Actually I am not using the previously mentioned shader for the background tiles as it's basically one big object generated by Tiled editor. I need to figure out the most effective way to detach the tile parts based on which palette I would like to use for specific tiles. Now, it just uses simple unlit alphatest shader comes with Unity. The big disadvantage of this is actually that I can accidentally use improper colour on my tileset, by this I mean, I my add more colours unintentionally. Other disadvantage is that I can't palette swap this way. One of the best thing with my shader is that is replaced red, green and blue colour by set colours based on NES's original palette. It doesn't allow me to accidentally use more than 3 colours per tiles, also the palette swap allows me to create cool effects like fading, day to night transition, see Simon's Quest... except the horrible night to have a slow text box.

Consideration: currently blue is the background colour. But it has some disadvantages. Just look at the edges of the cliff next to the tree line in the background. I could use a diagonal cliff edge tile there, but in that case, I would have a blue area. Of course, I could cheat by adding the black colour and actually that palette has it, but that would meant to add more unnecessary tiles to my tile set. As far as I know, some games uses black colour as background even if it's not the colour of the sky. Black is the ultimate colour for shading. It's possible to add the sky colour to the background trees and leave the black part transparent.