Darkness or Light? Philosophy in Knights of the Old Republic.

Regarding the lightsaber battle, it might not be the best, but I would say that Mace Windu is better than both Yoda and Palpatine in terms of lightsaber combat, but he's completely lacking in the Force.
Yes - in the end, Luke Skywalker would never have learned about his Jedi abilities, and Palpatine wouldn't have been thrown into the shaft on the Death Star))) Although, considering the intrigues that weren't shown in the film, it's quite possible that without Vader, Palpatine would have been overthrown... by Moff Tarkin or Admiral Motti... or eventually Grand Admiral Thrawn))) There were many contenders for Palpatine's position, but besides Vader, Palpatine also had many other powerful allies, whose stories were only revealed in the expanded universe... This includes the famous Grand Admiral Thrawn, Lumiya, viziers, and the personal guard... and much more, thanks to which Palpatine ruled the galaxy as Emperor for a good 25 years...

Interesting discussion, I'll add my two cents
The Sith are evil because they forbid feelings like love ("What could be worse than love? Only ONE thing - mercy" (Uthar Wynn)), mercy, compassion, the Sith condemn helping others, the Sith are ambitious, which means they are dangerous, the Sith are aimed at an endless cycle of violence and death (the student must kill the teacher... And here's the question - WHY have a student in the first place?! This, in my opinion, is the height of absurdity) and they use the Force for personal purposes, which, given all of the above, are not very good)
The Jedi are bad because any monastic order is bad - due to its isolation, but they at least help people...