The North in Italy is major in industrial strength i.o.t.l. With the backing of the Empire the south may be different.
A big impact already is the relatively lack of piracy. With the Roman East no source of piracy, and the sources of the Barbary pirates addressed/minimised by Carthage, Southern Italy sits at the heart of an economic powerhouse in the Med. It wouldn't surprise me if we discover Southern Italy begins to flourish with a number of Macedonian refugees travelling across to the now significantly secure southern part of Italy.
Regardless, overall this war is going to have some serious economic impacts for the Empire. We've got the security changes for Italy, leaving the rest of Italy effectively the secure western flank of the Romans with little piracy to worry about, and a long coast to trade on. We've got the depopulation as a result of the Great Transfer which is going to hurt, the depopulation of parts of Egypt, the demographic collapse of Syria, and the now-Roman N.Mesopotamian region. That's ignoring the explosion in bond-holding, and the acquisition of New World ports and the ability to engage in direct trade with Mexico via the Caribbean.
The Post War economics of the Succession War are going to be deeply interesting, and we've still got to find out how the Bavaria and the Wittlesbachs will hold out, and the fate of eastern Europe to decide. My Economics Nerd is excited!