Drew Karpyshyn said bioware did the foundry ending that way so they could go back to Revan again in the future. So I highly doubt Revan is dead at this point.
My original post said something along those lines. If they do have Revan come back, I would prefer him come back as a spirit and lend aid in the inevitable Emperor operation. Perhaps after destroying the Emperor's body, the spirit of Revan could have one lst battle with the Emperor's spirit. Maybe have a whole Reborn Sidious thing where Revan drags the Emperor's spirit to the depths of the Force. A fitting end for both of them.