Yes, they did have redeaming factors: Hitler liked dogs, and Stalin killed Nazis.
Just don't start sayin that all dictatorships are bad. Only hereditary dictatorships are inherently bad.
Stalin wasn't actually very particular about who he killed. The Nazis were a lot more circumspect than Stalin. Examine the history of both regimes and you find that Hitler killed lots of Jews, Gypsies, homosexuals, and a number of others of specific groups, but Stalin murdered by direct execution or by starvation entire populations within certain areas (see chapter 16 of Rpbert Conquest's book, "The Harvest of Sorrow").
Quoting a bit from the end of that chapter:
We may now conveniently sum up the estimated death toll roughly as follows:
Peasant dead: 1930-37 11 million Arrested in this period dying in camps later3.5 million TOTAL14.5 million
Of these:
Dead as a result of dekulakization6.5 million Dead in the Kazakh catastrophe1 million in the Ukraine5 million Dead in the 1932-3 faminein the N. Caucasus1 million elsewhere1 million
As we have said, these are enormous figures, comparable to the deaths in the major wars of our time. And when it comes to the genocidal element, to the Ukrainian figures alone, we should remember that five million constitutes about 18.8% of the total population of the Ukraine (and about a quarter of the rural population). In World War I less than 1 % of the population of the countries at war died. In one Ukrainian village of 800 inhabitants (Pysarivka in Podilia), where 150 had died, a local peasant ironically noted that only seven villagers had been killed in World War I.
Inherent badness? Bloody Mary (Mary I of England) got her rep from executing a few hundred Protestants. Ivan the Terrible had 30 to 40,000 inhabitants of Novgorod killed. Many other examples can be found of monarchs murdering their own subjects, often in cold blood. But no "inherently bad" hereditary dictatorship in Europe ended up killing anywhere near such large portions of its own populations during peacetime as the non-hereditary dictatorships of the Nazis and Communists in the 20th century. Better a bad king than a good Communist or Nazi dictator, in my not-so-humble opinion.
Said Dictator, not Monarch. I actually like some monarchies. And If I remember correctly, Ghengis's son was also voted as the head of the Mongol Kiyat, just like daddy Temujin. How's that for Democracy, eh?