Nah. The original plot involved either: 1) Luke falling to the Dark Side and leading away the remnants of the Imperial fleet to uncharted space or 2) Showing a scene after the battle of Yavin where both Imperial and Rebel fleets are destroyed; though the Rebels 'win', it is supposed to give the feeling of a Pyrrhic victory - no Ewok festival, no force ghosts, etc.
Lucas pretty much ran everyone off that was reeling him in at that point though. Keep in mind, this dude wanted a monkey wearing a mask to play Yoda - it was horrifying. Anyway, he pushed hard for the Ewok bullshit (ffs, we already had a Wookie character and his whole planet Kashyyyk, how much cooler of a battle would that have been right?), the second Death Star and the happy festival ending.
Return of the Sith was fucked more by editing than anything. The books / games show a lot of unaired scenes that were originally intended and it forms a much more coherent narrative.
Plagueis was a master though. Palpatine was a master. Anakin was a former Jedi master and war hardened general. Kylo is just a kid. Keep in mind, most lightsaber users didn't even specialize in forms of combat against other sabers by the time of the clone wars because the Sith were thought to be gone and the main opponent would be blaster fire most of the time. The best duelists of the time were Dooku, Windu and Yoda - Kylo grew up in a time with practically no one - just Luke.
Personally, I thought it was neat that Kylo and Ren displayed very rare, esoteric force abilities that were mostly noncombative. Kylo with his freeze and interrogation, and Ren with Pscyhometry - it wouldn't have made much sense if their saber styles were polished. Jango Fett in cannon killed many trained Jedi and even some in melee combat (he beat one to death with a goddamn rock); thinking that a young, green kid that was just shot by a wookie bowcaster had trouble with a soldier that was literally trained since he was a child to fight isn't too much of a stretch to me.
Ultimately, he completely ruined Finn anyway, so I don't see the concern. The complaints about Rey might make sense if she was like Rey Mothma or the child of some character we knew was a force scrub. As it is though, we don't know her background - she could be the Jayna Solo half to Kylo's Jacen, she could be a Kenobi, or hell, she might even be a Force Jesus like Anakin was.
