I'd say just lower monatery demands would not have made much difference. The Versailles Treaty's demands regarding annexations, military and so on would have still been enough to make the Germans feel disgraced. And the impact on the economy would not have been all that big either; the huge 1923 inflation and the generally bad state of the economy was not so much due to the Versailles Treaty, but mostly due to the depts made by the German government during WW1, which the new government had to pay back (and they then just printed money in order to do so).
So I'd say just lower monetary demands would not have changed much.
But assuming the Allies had been much more lenient when Foreign Minister Stresemann (1924-29, Weimar's relatively stable years) attempted to revise the Treaty by peaceful means, also regarding the question of lost territories and military regulations, thus allowed him a huge diplomatic success, that would have probably been a major push for the democratic parties and the Republic in general. The Nazis would have had a much, much harder time to rally so many Germans behind them in the late 20s and early 30s.
Stresemann (from the pro-republican DVP, German People's Party) would have become a national hero, and many Germans who later joined the Nazi Party would have likely rather stayed republicans.
There was only a short window for the Nazis taking power: Their peak of popularity had been reached in early 1932 already, when they won 37% in the elections. Their popularity was about decreasing already, they won only 33% in November 1932 (their first loss of votes compared to an election before), when President Hindenburg named Hitler Chancellor. Had the Republic persisted only a few more years, there is a good chance the Nazis would have fallen down to a minor faction once again.
More lenience by the Allies in the 20s might have been just the push the Republic needed.