Do you mean in terms of conversion work? I am not sure I am ever deeply impressed by color choice. Conversions impress me, but if this guy is legitimately trying to represent Kurt, then he is sort of locked into what he can do.
I'm not sure i can say one particular aspect such as "conversion" or "colour choice".
This will probably boil down to personal taste preferences soon, but just for the fun of it, let me try to explain by giving an example from the B&P.
It is an example of both technical skill and "conceptual skill" or whatever we should call it, which made quite an impression on me: cjp's Reiksguard foot knights (I hope cjp is fine with me using this example).
Look at the use of many different colours and contrasts, the use of both NMM and MM and the freehand goodies. Consider the clever use of symbols from occultist societies, which opens for associations of the Reiksguard to mysterious, secretive orders with their own symbols and rituals.
This paint job does not just express "what we know the Reiksguard looks like". To me, this is "what you had no idea that the Reiksguard SHOULD look like". It is a personal interpretation, a suggestion if you like, with consequenses even for fluff et c.
The Helborg job - as wonderful as it is - is still just "what we know that KH looks like". The artist's purpose is probably to use a perfected NMM technique on a model that lends itself well to it, not to make personal interpretations of a concept. This is, of course, perfectly legitimate and in itself an interesting project, but such a purpose will necessarily lead to a result with fewer dimensions. We can admire the technique, and the artists understanding of reflecting light, but there is not much more to admire.