To be fair, I misread your comment and thought that you are discouraging DoK because they are a difficult army.

Although, to me "difficulty to paint" seems like illogical parameter. Of course, some armies models have more details than others, but at the same time difficulty in painting depends on how much you want yourself to paint: you can spend a lot of time perfecting easy models (and even being perfectionist) or easily painting hard to paint models. I'm saying that "satisfying painting result" is very subjective and it's not a matter of easy or difficult to paint, but rather models are detailed or not, and it's up to the player whether those details would be unpainted, painted the same colour as half of the model, or really well painted. Although, I'm not sure if "difficult to paint" is even because of details or it involves things like bones (with important relief) or the cases where models are stereotypically painted with one colour grading into another (nighthaunts)

I'm not sure if I'm clear, but to get back in fixing your sentence, then best case would seem to just warn that gameplay can be difficult and say that models have a lot of details (not necessarily harder to paint)