You need to utterly alter the way that Hitler saw the world. Doing that will almost certainly result in the "Hitler who?" scenario where no one has ever heard of him.
His hatred of Slavs was deep rooted, close (and related, BTW) to his hatred of the Jews.
As an example: His goal was to WIPE OUT the Polish people. Kill off 80%, most by "extermination through labor", and ensure the survivors be kept as illiterate chattel slaves to ensure the Polish language died out. He also intended to take every great "Slavic" city and quite literally demolish them down to the last brick (part of the extermination through labor noted above).
Hitler without hatred = No Hitler as Fuhrer.
I think the idea of "Hitler as a hate machine" is over-rated. For one thing, Hitler wasn't the most consistent racial theorist - his opinions seem to have shifted depending on what his mood on that day was and what the opportunities of the moment offered.
For example, Hitler promoted the Japanese several rungs up his racial hierarchy when they became one of the handful of countries willing to ally with him.
In the particular case of Slavs, he seems to have changed his mind several times as to what he actually meant by "Slavs". While Russians were always "bad Slavs" (except for during the Nazi-Soviet pact), pretty much every other kind of Slav was given status as "Slavicised Aryans" at some point during the Nazi regime (note, "Slavicised Aryan" status could and was removed as well - generally by sending in racial profilers who analyzed the skulls of the locals and came back with a result that said only a tiny proportion of a population was "Aryan", opening the door to liquidating the rest if so desired).
The Nazis really loved the Sorbs for example as well as the Masurians (East Prussia's protestant Polish population).
Hitler also wedged Croats into the upper levels of his racial hierarchy after Mussolini pushed him into invading Yugoslavia. At the same time, the same situation made him demote the Serbs drastically.
And then, with the Poles...
There's this quote from 4 March 1944 in a memorandum from Hitler to Himmler: "Poles are the most intelligent of all the people with whom Germany came across during the war in Europe... Poles in my opinion and basing on the observation and reports from the General Government, are the only nation in Europe that combines high intelligence with the incredible cleverness. They are the most talented people in Europe, because while living in extremely difficult political circumstances, acquired the great sense of living, unparalleled anywhere."
I've also read in second hand sources that Hitler spoke favorably about Poles in Mein Kampf. This may be hearsay mind.
Certainly when Hitler first came to power, the Polish government was quite excited, since Hitler spoke about Poles and Poland in much more respectful terms than _any_ of the Wiemar chancellors who had preceded him (peace-loving Wiemar Germany, yeah right!)
However, Poland, with its will to stay neutral in the German-Soviet argument and with the political gasoline of existing German (and particularly German _army_) prejudice against Poles, was easier to annihilate for Hitler.
I don't think Hitler is an exception to the banality of Nazi evil. I don't get the sense he was a man driven by demonic hatred. Rather, to me he simply comes across as a man who could rationalize away inconvenient moral boundaries that lay between him and what he wanted (a German Empire with a "revitalized" and Nazified culture). (Meaning hatred was a means to an end for him, not the end towards which he worked.)
As such, while I agree that there is no way for Hitler to fit Russians into his idea of the "family of Aryan peoples", I could see him fitting Poles and Ukrainians into the "Aryan family".
I don't think that would make much difference though. Hitler would still go East with the army he had, that army is extremely likely to act out on the witches brew of Polonophobia that had been steeping during the Wiemar period, meaning that however "Aryan" Hitler tells the troops the Poles are, abuses will still happen and relations between Pole and German will go down like a lead balloon. Similar in Ukraine, where avoiding the bad racist crimes might improve things in the short term, but in the medium and long term, fighting the bloodiest war in all of history on Ukrainian soil is going to result in German atrocities against the civilian population, sending those relations straight down the toilet. In both cases, collapsing relations between occupier and occupied (or puppet ally and Reich) is going to mean Aryan status is removed from larger and larger groups of Poles and Ukrainians.
fasquardon