Episode VII has, by order of magnitude, the best lightsaber battle in the series. The only real contender is Episode VI's duel, where Luke lets himself touch the Dark Side and is passionately hammering away at Vader like a blacksmith working at the anvil. There's three films worth of pent up narrative exploding in that fight, and it's impossible to discount it. But Episode VII...oh my.
The snow, the slowly dying light, the bright primary colors in the darkness. Kylo Ren's haggard, stooped over and violent slashing...a fundamentally erratic and unstable character becoming more so after the murder of his father. Rey struggling to come to terms with her awakening power/memory, first using the saber like her more comfortable staff. The weight of the sabers, the crackling, the sparks and snow flakes flying around in 3D. The implicit familial relationship between the participants unspoken but heavily foreshadowed, culminating in Kylo Ren attempting to turn Rey in his moment of victory rather than dispatching her. Even his swift defeat of Finn had plenty to love...Finn's desperate resolution despite being hopelessly outmatched, Kylo Ren pounding his wound to wind up his anger and pain. Absolutely spectacular, and easily the best sequence in the film.
Comparatively, the prequel fights were a sorry joke. They were a joke all on their own (for reasons already amply covered in this thread), but Episode VII's fight helped spotlight just how bad they were. Weightless, zero-emotion, over-choreographed prancing. In a few of the fights it was an actor waving a stick around at literally nothing, with their opponent added in later via post-processing. Hey Ewan, stare at this tennis ball and pretend it's Grievous walking towards you swinging a hundred lightsabers. No one knows what to do or how to react. It looks fucking terrible. It's pretty common for people to be openly scornful of the prequels (with good reason), but there is a bone occasionally thrown to them that "at least the lightsaber fights were cool". They'll point to Obi-Wan and Vader stiffly exchanging blows in A New Hope and then to the airy twirling in Phantom Menace and say "See how much more exciting?". Except Obi-Wan and Vader's "duel" was never about the sabers, Obi-Wan had no interest in fighting Vader and his sacrifice was both an important narrative beat and an essential thematic beat for the series as a whole. When the inscrutable Qui-Gon Jinn dies and McGregor gets an opportunity to emote at something that isn't a tennis ball or a mark on a wall for a change, what happens? More weightless, passionless choreography. Spin and slash at the air. Prance and slash at the floor. Even the choreography, while overwhelmingly PRESENT, is terrible. Maul, please stand gormlessly while your opponent gradually flips over your head, pulls their saber into their hand, and disembowels you. Maybe slash pointlessly at the floor a bit in the interim.
Do you recall Anakin in Episode I? The "Let's try spinning, that's a neat trick" line? That pretty much sums up the battles. "Let's try spinning, that's a neat trick". Calamitously bad. Offal.
