Hitler was known to promote 'Aryanism' - the Blonde, Blue Eyed, Fair Skinned German. In fact his scientists conducted tests for Aryanism - which separated the pure Aryans from the Jews and others.
Yet I have always thought there was a certain 'Jewish-ness' or 'Asiatic-ness' about Hitler himself. The dark eyes, the thick dark hair, the large nose. Seriously in some photos he looks very very Jewish, and I don't know if this is proven fact but some quarters assert he did have some Jewish ancestry.
But didn't any critics in Nazi Germany or outside it ever remark on the irony of a dark haired Hitler promoting a pure blue eyed and blonde haired Aryan race when he himself might have failed his own 'Racial Purity Test' simply on his appearance alone?
There's a lot to unpack when talking about Nazi racial theory, so I'll try to keep this targeted.
Hitler himself had dark hair and blue eyes. I'm not sure what 'dark features' you're meaning, but in a moment I'll show why that's neither here nor there. As for his alleged Jewish ancestry, I don't have any knowledge on that so I'll refrain from addressing it.
A lot of people misunderstand what an 'Aryan' really was considered to be. Blond hair, blue eyes, tall, good posture, etc., yes. But those were more or less ideals than actual realistic standards for determining if someone was an 'Aryan' or not. For instance, in The Official Handbook for the Schooling of the Hitler Youth there are 6 different 'Aryan' sub-races native to Germany alone. The differences between these races were things like hair color, hair texture, and shoulder width. So lots of Germans without blond hair and blue eyes were still considered to be just as 'Aryan' as the stereotypical tall, blond, blue eyed Scandinavian.
Moreover, there were different kinds of Aryans described in the Hitler Youth handbook. Mediterranean Aryans were made up of southern Italians (Northern Italians were considered a part of the Germanic races), Greeks, Spaniards, etc. Asiatic Aryans (I believe that's what they were called, but I don't have the Hitler Youth handbook with me) were people like the Iranians (at the time referred to as Persians). And of course the honorary Aryans, the Japanese, though they hadn't been described in the handbook. In the handbook there are diagrams of the skulls of all of these 'Aryan' races (but not the Japanese).
So the definition of what physical characteristics distinguish an 'Aryan' from a non-'Aryan' was actually very complicated and often contradictory, even though logically speaking it should be the most clearly defined race of all in a society based around it.
But now you see that the Nazis bestowed the title of 'Aryan' to many groups of people, of which many didn't generally have blond hair or blue eyes, weren't known for being particularly tall, and certainly weren't Germanic.
Hitler's appearance was perfectly acceptable to be classified as an 'Aryan.' Blond hair and blue eyes were more just unrealistic ideals for many people, and dark hair and dark eyes were in no way deal breakers.
As for critics of Hitler's appearance within Nazi Germany, I wouldn't be surprised if there were some, but because the definitions of Aryanhood that I laid out above were so much more well understood within Germany as opposed to outside it, those critics would have been rather few and rather unimportant.
Source: Official Handbook for the Schooling of the Hitler Youth