Tbh he seems to have achieved immorality and an entire empire worshipping him and serving his will. He praises himself for having "the patience of stone and will of stars". He didn't spend decades same as a character in their 30s, 40s etc. with the worry of limited time and resource. So, saying that he sucks cause he gets overshadowed by characters like Sheev in time efficiency is kinda unjust since Palpatine isn't written as an immortal character (especially since he is originally a movie character), who at the same time is arguably the smartest and the most successful character in the lore.
Can't disagree that Vitiate's a ripoff and his story is ridiculous compared to what we see. I enjoy his dialogue though.