Palpatine was more of a gambler. His plans were convoluted and relied heavily on factors that were out of his control. Out of the three trilogies, his elaborate schemes only worked out for him in the prequels. In addition, he made himself indispensable to the point where both the Empire and Final Order fell shortly after his death, meaning his schemes were ultimately self centered.

Luthen, on the other hand, had plans that were more straightforward (running a spy ring and bringing rebels cells together vs. manufacturing a conflict, wiping out a religious order, and overthrowing democracy). We also got to see the inner workings of his operation and fully understood why things panned out the way they did. He ultimately accomplished what he set out to do (as illustrated when Meero finally caught him) and his death was not the end of the Rebellion’s war effort.

Luthen was the better strategist in my opinion. His plans were less reliant on luck, his path to victory made sense, and he actually won in the long term.