Let me elaborate, by process of refutation.
These are the palette templates that over the years, I've only seen decently executed by experienced hackers.
I. Changing the time of day. So, you want your GHZ to have a sunset feeling going on? Or you want your EHZ to be during the night? STOP RIGHT THERE. These will be your first mistakes. These two ideas should be avoided for two reasons:
A. They're very awkward to do if you're new at this. Sure, maybe the checkers will look a little lighter orange, but the grass might look like glowing radioactive stuff.
B. They're generic and over-done ideas. Seems like only the experienced hackers can make these two ideas look fresh nowadays.
Totally disagree. Like, we couldn't be more polarised. This is one of the best ideas a beginner can try to implement! Why? Because the base palette is already there, so the fundmentals of colour theory are there for you to experiment with. And learning how light affects colour (in this case, figuring out how the sky colour/time of day affects all other palette entries) will strengthen the colour theory in general anyway. And I'm biased because S-Factor's first zone, Spectra Valley, started as a sunset edit of GHZ. :3
These are colour edits that I've never once seen done well. They mostly aren't used by experienced hackers.
I. Making the grass some weird ass colour. It seems that only shades of green fit for grass because, well, it's grass, stupid. Making weird coloured grass makes your hack look too odd, people won't be familiar with weird colours, therefore, people will subconciously lose interest in it. It'll look like Sonic is on some alien planet.
Palmtree Panic Bad Future is an in-canon example of you being wrong there. It can work in context.
Star Light is mechanical, man. Also, as long as the grey is complemented and/or contrasted with an otherwise decent colour selection, it can work as well as any other hue. It is as valid as any other.
Don't do this. Seriously. Start with the base colour as a mid-tone, and then work out the highlights based on the colour of the light source or sky. Then work out the shadows based on the complementary colour; and NOT one from a RYB colourwheel - we're dealing with light here so it's RGB or GTFO. Shadows of a colour are generally a lot stronger than simply making the base colour step slowly to black.
On this I do agree. Nice try for a helpful post, but I dare say a better understanding of colour theory in general would be better than following these tips.