Moto G4 and G4 Plus are now available in the US Moto Maker website with a plethora of customization options
Well, in all fairnes, the choice may still seem a bit limited to some. The front panel can be either black or white (dark moon or metallic silver), and the trim is always gray-ish metal. There are 8 different colors to pick from for the back, albeit most seem dark and bland. The accent option adds a different color for the camera trim, with 5 options to choose from. Additionally, one can have the phone's boot screen greet them in a unique way, which is a nice touch (though, be careful with that greet message if you care about re-selling the phone later).
You can check out some of the possible combinations below, or hit the source link to visit the Moto Maker website and make your own!
source: Moto Maker
Things that are NOT allowed: