It seems like both the Kurdish and FSA/Turk forces want the important city Al-Bab. The question is who will reach it first?
YPG will not advance west of Euphrate. YPG is supposed to withdraw towards the eastern Euphrate bank. They don't really do. Without coordination with the turkish dominated FSA, they'd leave a vacuum easily to be filled by ISIS again. They want to keep Manbij and they will do at least for the near future.
So... Who do the war gods favor in this war as of say the last 2-3 months? Who is having a good time and who is having a bad time?
SAF: Okay time?
FSA: Kinda shitty time?
IS: Very shitty time?
Kurds: Okay time?
Am I getting it or totally not?
The long-term prospects changed radically. There is a new player in the game. That is the biggest change. The Free Syrian Army is closely linked with Al-Nusra/Al Qaeda/Fatah Al-Sham. But now Turkey is directly fighting alongside the Free Syrian Army in northern Syria. The turkish influence assures that the FSA units supported are actually 'moderate' and not radical islamists. Thus you got 2 Free Syrian Armys now. The Al-Nusra dominated FSA in Idlib and the turkish FSA in northern Aleppo. The turkish FSA is the actually new player. This player will rise. It is likely that Turkey will route moderate rebels from Idlib to northern Aleppo through their territory, until there are only radical Islamists in Idlib left.
Syrian Arab Army: doing OK, arms are being provided by Russia, manpower by Hezbollah and Iran. Good long-term prospects. A serious winner.
ISIS: doing bad. Less income, less territory, nowhere to hide. They are being pushed back to core territories currently. Point is: They're withholding professional western arms and elite forces for later to fight in their core territories along the Euphrate river. They're not dead yet. Far From. But they will have no future in Syria.
turkish FSA: will become a major player in northern Syria.
Al-Nusra FSA: declining. Bad long-term prospects. Will bleed dry if Erdogan wants them to. Is an enemy all major players can agree to get rid of.
Kurds/YPG: stable. Might get soon in favour of the USA over the turkish FSA who proved being bad playmates. If the USA stop all support on turkish FSA, there will be more to get for them.
3 goats, 3 ISIS fighters. I'm just not sure, who is who.