Part of the problem with the PT onwards. The Jedi & Sith were actually extremely interesting in the OT and part of what made them interesting was that their powers were reasonably limited.This is my main gripe with Star Wars. Nothing trumps a Jedi. When a Jedi is on screen, all non Jedi combatants are rendered useless. There is no in universe being as powerful as the Jedi/Sith. Lucas had a fantastic opportunity to rectify this with Grievous, but her got nerfed before he even got to the movie (by a Jedi who didn't even fight him! Force crush. Yawn.)
When I watched the OT, I thought being a Jedi was about more that the sword. Yoda never even touches one in Empire, and all of his lessons to Luke have to do with the Force, not the Laser Sword. Conversely, Palpatine calls the Light Saber a "Jedi weapon" and seemingly has no use for it, as his force powers alone are far mightier than some stupid sword. Fast forward to the PT and both characters are swinging away. It's so boring.
How does the series fix this? I think it's simple - make Jedi/Sith characters who fight strictly with the Force. Not every Jedi needs a Light Saber. Also, it would be nice to see a non Jedi character who can hang with or even best a Jedi in battle.
*Starts countdown to somebody saying "well, in the expanded universe..."