I think it looks better like that than it might in green.
As we've seen on the Jaguar F1 cars, green just looks naff on a modern single seater (IMHO).
They could have chosen to copy a classic british team livery though, e.g. JPS/Olympus, Yardley, Martini Brabham, etc. They needn't use the actual sponser, but imagine a JPS coloured entry for the UK