What are the best camera settings for the phantom 3 standard (resoloution, colour mode, etc)?

Just as there is no one best photo, there is no simple best  settings.
If there was, camera makers wouldn't provide so many settings.
But if you're not expert at manipulating camera settings just leave it in auto and most of the time it will make less of a mess than you might.

Whatever the highest resolution it lets you. Shoot in 4:3 aspect ratio (16:9 is just a 4:3 cropped in camera) and use the lowest ISO you can get away with. For Color mode, it depends on what you are shooting, choose the appropriate mode for what you are shooting, you can see the change on the screen so just play with the different ones if you are not sure.

If you can shoot .DNG (I don't think the standard can?), use it, it allows for much more editing and correction then .jpeg does. If you use .DNG, it doesn't matter what colour mode you use, as you can just change it after the fact. With JPEG you can only make small changes to colour, so you need to get it right before hand.
Edit: Standard can shoot .DNG as per below post.

labroides@yahoo Posted at 2016-2-3 07:21
Just as there is no one best photo, there is no simple best  settings.
If there was, camera makers w ...

Well said^

pantera989@gmai Posted at 2016-2-3 07:38
Whatever the highest resolution it lets you. Shoot in 4:3 aspect ratio (16:9 is just a 4:3 cropped i ...

nice suggestions!  Standard can shoot DNG as well