The Treaties the Germans imposed on Europe were and would be much harsher than Versailles. To the point that nobody could threaten Germany.
That could work only against France (in addition to Brest-Litovsk). If they were too tough on Britain, Britain would just keep fighting (Germany can't cross the Channel without a major naval victory), until the blockade wrecks the Kaiser's economy. Ukraine wasn't enough to fix that problem, and was basically in civil war anyway.
Regardless, Germany's economy will crash at some point not long after WWI finishes (anywhere from 1918-25), because of the loaning system that was used to finance the war. That will weaken Germany's power to enforce a treaty, and I think there is a good chance that Russia could get Ukraine back (though not Poland/Baltics).
Would the USSR really be dumb enough to start away against Germany, all of its Eastern and Central European satellites, and the remnants of Austria-Hungary and the Ottoman Empire? I can't see any advantage they would have.
Depends who is leading it. If Stalin thinks he has half a chance of winning, he'll go all in (Finland anyone?). Lenin probably even more so. Can't say for the other leading Bolsheviks, but there were probably some who wouldn't fight.
Also, for both the Ottomans and AHE, either they stay together (German intervention before the economy falls) or they break apart and everyone in them is fighting each other, rendering each little country too weak to do much. At least compared to the USSR.
Versailles didn't fail because it was a bad treaty (any treaty coming out of the WW1 mess was certain to be bad) but because the victors were to weary and divided to enforce it. If the Germans were willing to make the effort needed to enforce their peace, they could most likely have done so.
Germany was weary of war as well, and France in particular would be absolutely livid about losing another war to Germany. The harsher the conditions, the worst this gets. Also remember that Ludendorff thought that Brest-Litovsk was creating unnecessary obstacles for his 1918 attack (having to leave a million garrison troops in the east).
So either the treaty is kinder to everyone but France, or it falls apart. I can't see Germany maintaining itself in a position of power through such a crisis if the UK, France, Italy and some of the AHE's breakaways (Serbia!) decide to oppose it.
- BNC