Of course Charles III would need to renounce his succession rights to 'Austrian' titles as part of the peace settlement granting him the Spanish throne, exactly as Felipe V had to renounce his rights to the French throne in OTL. Of course there still would remain the negotiations among all parties as to what territories would comprise Spain and 'Austria' as well as any possible compensation to other powers. In this era there are no diktats to settle great power wars. Sauce for the goose, sauce for the gander.
Once the war started, it's going to take a crushing victory to remove France from the war. This basically happened in 1709ish. A great famine, no money, military losses all combined to cause Louis XIV to beg for peace. He was willing to give up everything: his proposal to give Spanish Netherlands to Maximilian Emanuel for losses in Bavaria was shot down, he was willing to abandon Philip. Britain insisted (stupidly) on France assisting in removing Philip. Louis felt France had nothing left for such an effort, and found the notion appallingly unacceptable. Then Britain started angling for itself at the expense of its allies, and France found a second wind to fight on, Philip proved capable of holding Spain without help, and Joseph died, leaving Philip as more desirable than Spain and Austria under one King. OK, enough of a preamble.
If France is crushed early, before Philip is firmly rooted in Spain or Austria in Italy, we might see some Italian Kingdoms going to Philip. Britain doesn't want the Habsburgs left with everything. By 1709, though, Philip needs to be forcefully removed, and Austria has control of Italy, meaning they have to be forcefully removed (Austria wanted it all). The only scenario I see of Philip/France getting anything in compensation is IF France turns on Philip in return for his gaining a Kingdom in Italy AND Austria can be convinced to give up Italy. Hard to envision either one happening, let alone both.
Once the war started, dividing up the empire and giving a piece of the pie to Bourbon was increasingly reduced. Savoy might wrangle a bigger piece, though.