For a long time we have used only a white all around light on the stern with no issues and you can mount it to the transom or have a removable one
For a dink of under 7 meters , the white all round is legal and usually easier to mount to the transom , and remove than glue on.
It aint "legal: but for ocean work we use a white all round at the masthead, boat is 33ft , about 10 meters.
Reasoning is outside distance long light is required for the big guys to happen to pass thru the wheelhouse , or perhaps turn a spoke to avoid you.
What does white all round mean to the viewer at sea?
Small boat , you are running up on.
Anchored boat , You are running up on.
Stern light , you are running up on.
All require a miss action from the viewer.
AS the Esso Maru , and her sisters are running 20K+ our sailing 5K or 6K is anchored for there purposes , and I dont worry that they would pass a 7 meter boat so close that my 9ft is at danger of hanging in their path.
Green or Red absorb almost 90% of the power passing thru the lenses, so for us the choice is easy.
Not the way we travel in inshore waters , but 1/2 way to Martinique , it saves juice and might save US!
FF