As a major stronghold in the middle East, Raqqa needs to be taken for any kind of Kurdish victory against ISIS to occur. ISIS holds Raqqa and most commentators consider it to be an important city to take.
If ISIS keeps Raqqa they will have a permanent foothold in the Middle East, this will allow them to keep growing and exist for even more years than many have predicted. If the FSA takes Syria then they will be simply another militia in the area that murders innocents can keeps the war going.
If the Kurdish win then they will have taken a major stronghold and all of their enemies will suffer, probably leading to the end of the war, and also achieve autonomy for their people so that is an upside
Russian president is trying too hard to help save dictatorship in this particular country being afraid of his own position. Many people died because of Syrian and Russian's presidents cruelty. It's time to show strong will for U.S. if they want to prevent any more deaths, especially now, after new information about Flight MH17 was revealed and it's a slight chance to win this round with Putin.
Yes, Syrians will know peace in the foreseeable future because their crisis has come to the world's attention. Thankfully countries like the United States want to make Syria conflict free as soon as possible. It will be difficult but so many people are working toward a solution that it will be accomplished.
New Aleppo attacks definitely threaten peace. If Syrians are using Russian warplanes and weapons and Russia continues to supply them, more hostility can't be good for any peace talks. Although each time there's a ceasefire, people can hope it will finally take hold. However that's happened so much, that hope is fading.
Maybe if the United States takes its ball and goes home and leaves the Middle East, Syria will know peace. Since there's no chance of that happening, the poor people of Syria will continue to pay for the arrogance and mistakes of the rest of the world. Syria is nothing more than a proxy flexing contest between the United States and Russia.