<I>Would a Central Powers (as in OTL; Germany, Austria-Hungary, Bulgaria, Ottoman Empire) victory be for the better of history?</I>
Under what circumstances and when does the CP get the victory? If Germany sweeps into Paris in September 1914...
http://en.wikipedia.org/wiki/Septemberprogramm
But if it must involve an additional two years of war then harsher penalties will be present. I expect Germany might then annex Luxembourg, Belgium east of the Meuse, and maybe set up a puppet government in Franche-Comte. Also, the rest of Europe will be turned into very pro-German satellites. Austria will implode and the German speaking portions of it will join Germany itself, probably along with Bohemia which will be slowly assimilated.
<I>Many scenarios of a CP victory in WWI have a neutral US with an eventual CP victory. In all seriousness, what
would happen?</I>
Germany is likely to lose if the US gets involved, it becomes much harder to win with a continent-spanning opponent joining your enemies. It also means the US rises but more slowly.
<i>As for France, the most humiliated of the Allies, there would be large indemnities and a large occupation zone. From what I've read, France has neither the capacity nor the conditions necessary for a far-left "Communist France" nor a far-right "Fascist France". Even if a revanchist regime was established, I doubt the Germans would tolerate it even for a minute and would take necessary actions unlike oftentimes OTL allies against Germany. France would lose many overseas territories, though the remaining strongholds, such as Indochina, could erupt in full-scale revolt against a weaker France.</I>
France would already be asked to pay dearly but much of her industrial capacity would be lost in the territory ceded/occupied by Germany. Expect a fascist dictatorship to rise as the Third Republic falls because of its failure to retake Alsace-Lorraine and its loss of additional territory. This new regime will find it very difficult to rebuild nationally and would probably require loans to do so, possibly from Britain or the US (I doubt they would accept German capital).
<I>As for Russia, there are many German puppet states that were established from the Eastern Front. With a buffer of CP-friendly states separating Russia from Germany and Austria-Hungary (the latter would ruin hopes of a last-chance Pan-Slavist movement), an extremist Russia could be choked off.</I>
Not necessarily, these "Cordon Sanitaire" nations are not likely to be huge fans of Berlin either. While not as bad as Nazi occupation the idea of cultural superiority was still there and German will be taught while local languages will be highly discouraged. Though there will probably be a lot Yiddish and Hebrew speakers in generations to come even if Israel does not exist.
<I>As for Britain, the least humiliated of the Allies, there is not much territory lost. Troubled with defeat on the continent, the British instead focus on maintaining their empire (still probably the largest overseas empire in the world), namely India, and shy away from the continent, much like pre-war. Due to the possibility of not having to cede territory, an Anglo-German rapprochement is likely by 1940.</I>
UK nearly went socialist regardless in the strikes of 1926, if they end up losing the war early then I doubt they lose much other than some trade privileges or basing rights. After a long war they
might sell a colony or to Germany (more likely they demand African colonies from Germany as a price) but even then it will not come cheap, Germany has no means of projecting power to the sea and both sides know that.
<I>As for Austria-Hungary, despite their occupation of Serbia, they are forced to withdraw due to impending internal struggles. However, the nation is free to establish liberal reforms, which are encouraged by the creation of nearby nation-states such as Ukraine. Internal struggles in A-H are probably the greatest struggle for the Central Powers during the late 1910's to the early 1930's, thus beginning a new age of warfare, much like OTL "fourth-generation warfare". Many regions would wish to secede from A-H (namely Galician Ukranians who would like to join Ukraine), and this goal's possibility depends on the CP's treatment of internal struggles. More leaders like Franz Josef would probably leave A-H in ruins, though.</I>
AH is dead, the question is only when. Expect Austria and Bohemia, maybe Gallicia too, to move into German control while the Hungarians set up their own state out of most of the leftovers (OTL Hungary + Transylvania + Croatia, +/- Bosnia, +/- Slovakia). Romania would likely be a German puppet either way and probably unaffected. If Gallicia wants to join Ukraine badly enough it might even be accepted by the powers in Berlin.
<I>As for the Ottoman Empire, the nation begins a slow decline despite victory. I could see the empire collapsing just to the approximate area of OTL Turkey by 1935, and the Germans may encourage the decline as they want to gobble up territory for their own economic use (even Britain may as well). </I>
I disagree that this is a certainty, there is enough impetus to reform the nation that the Ottomans might survive, and they might also get some territory as a peace condition with Russia. If they have Azerbaijan then the oil money from there will certainly help.
<I>Last but not least, as for Germany, the nation goes on a massive reconstruction program. Germany most likely becomes more liberal over time (especially with the passing of Wilhelm II), and with the stabilization of France, Russia, and Austria-Hungary, the Germans withdraw from the former Eastern Front to allow independent development of the countries, though they remain in a sort of "economic zone" with Germany and Austria-Hungary. With a German victory, there is no Nazism as we know it, and an equivalent isn't established in France or Russia. Perhaps Italy remains a threat, especially to Austria-Hungary, but all movements for war are unpopular.</I>
Italy is likely to keep most of what she already has unless things move later into 1916 or so, but then unless Venice is occupied her losses will not be that much. She will eventually be brought into the German fold as a stronger satellite. Germany will rule the continent and become a dominant language of education, commerce, and engineering in Europe. Without the problems of reparations and loans there might not be a stock market bubble and thus no Depression, but expect technology to keep developing. Germany will not allow any power in Europe that would compete with its own and look for Russia to see the Whites supported by Germany if at all possible, Berlin wants to see Russia tear itself apart or at least be weak enough to deal with if a future war develops. If the Russian monarchy survives it would not be surprising if one of the Russian princesses marries a Hohenzollern. But WWII might be avoided entirely, and along with it a massive delay in the Civil Rights Movement, decolonization, Women's Rights, the Space Program, nuclear technology, and a lot of the things we take for granted OTL.