Can I move the range hood but not the roof vent (angled "flue" pipe)?
Putting the stove in the corner like you propose also gives you some nice space to work with for routing the pipe up into the ceiling / roof area or out an exerior wall. 

Seems to me that re-routing the vent to the previous riser location is a total non-starter. Many hoods vent up into the small cabinet above the hood and your re-routed vent pipe is going to make a mess of the upper cabinets if it has to route nine feet across your kitchen.