A cease-fire, even a partial one by only some of the parties to the war in Syria, is the perfect first step -- but only if it's widely understood as a first step.
Almost none of the news coverage I've seen speaks to what purpose the cease-fire serves. And most of it focuses on the cease-fire's limitations and who predicts someone else will violate it, and who openly promises to violate it. The big outside parties, or at least Russia, plus the Syrian government, will go right on bombing selected targets, which will go right on shooting back, while Turkey has announced that ceasing to kill Kurds would just be taking the whole thing a bit too far (Kurds the United States is arming against other people the United States is arming, by the way).
The United States distrusts Russia on this, while Russia distrusts the United States, various Syrian opposition groups distrust each other and the Syrian government, everybody distrusts Turkey and Saudi Arabia -- the Turks and Saudis most of all, and U.S. neocons remain obsessed with Iranian evil. The predictions of failure could be self-fulfilling, as they seem to have been before.