So basically unless some skill yet to be seen shakes the rotation it seems it would go like this:
Ecurasia dosis 3-> Phelgma->Phelgma->Dosis 3 spam-> refresh dot->Phelgma on cooldown
Switching Dosis 3 spam with Toxicon 2 when we want to move more and double weave

Its not good but at least its better than Sch's current rotation, especially if we consider a party member buff we're yet to see