"You speak as though you will live that long." For there to be a new Jefi Order. Something Malgus does not want. No more Jedi.

"As for the Sith. I am going to recreate the order from the ground up as I intended in the past. And I will destroy your Emperor and the Empire will become my own." With his rules and ideals.

Even if he has to kill off half of the people in the Empire to achieve it.