While in many ways the two sides were equally "horrible", the Entente victory (to which the US entry significantly contributed) brought freedom to many, just to mention Czechoslovaks, Yugoslavians and Poles.
Also, as far as the colonialism is concerned, the WWI was one of the first step toward end of the colonial empires. Yes, it was a very long process and it took another WWII to produce more visible results, but it shook the fundamentals of the imperial world order (for example, Britain's loss of the foremost position in economic affairs). So yeah, things weren't so black and white.
Yeah, about the only oppressed European group who
might've been better off in the event of a Central Powers victory would be the Irish. And even that as doubtful, as Irish Independence was probably on the Kaiser's list of priorities somewhere between taking the spike off the German helmet and shaving off his sweet 'stache. Which is to say, it was a pretty low freaking priority. The Central Powers weren't really fans of empowering the lowly nations of Europe, though in the case of Ireland there could be a pretty strong advantage to having an inherently anti-British state on the side of the Germans if another struggle comes up. In that case I could see an Armistice Treaty where the British are forced to give up Ireland and the political functions of the First Dail and the Senadad are allowed to continue without British interference. And of course there is the possibility that the British refuse the Treaty and the Central Powers intervene in a possible conflict in Ireland that could result in a permanent German occupation to prevent "future intrusions" that ultimately ends up with an Irish state that becomes a puppet state to the German Empire. And that's if the Germans aren't too busy with the Soviet power they helped install to their east.
I of course would still be against the war had I lived back then, but the Central Powers certainly weren't morally superior on the whole topic of minority rights.
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