yes Kylo ren may seems disappointing at the end fight scene given such a powerful start , however i enjoy the fact that kylo is still actually a padawan that had yet to complete his TRAINING as snoke said. so he is not any much better than rey.
Rey who had no formal training may already lived with the force and use the force like Anakin did when he was a boy in podracing. After all being a scavenger she had likely use her inborn force power without knowing like how she pilot the falcon with super fast reflexes.

during the fight between kylo and rey, kylo dont want to harm rey, he wanted rey to become his disciple while rey wanted to kill/injured rey for killing/harming 2 of her close friends (u know who).


But i look forward to what Rey and Kylo would become when fully trained (by snoke and luke). So i hope the next one will need to be a much better sabre dueling not like this one.

For ep7 what was made was made. It was a tribute to fans and it was well done. New fresh characters of rey, finn , BB8 is memorable and fantastic to follow...
very nostalgic of ep 4-6 which is good since 4-6 was a looooong time ago and even though 7 seems like a mashup of ep 4-6 it was great cause 4-6 was the best trilogy. Nothing wrong with using a proven winning formula to reboot. But ep8 would be important to set it apart.

what can be improved in ep8
1) Captain Phasma, the commander, and Kylo need to be much better. More darker, more bad ass. (right now too wimpy - Disney sign...)
2) POE is fantastic as a pilot, but he need more screen time to develop his character should he be the next hans solo.
3) more dueling with lightsaber .. (epic ones like Knights of the fallen empire.. those cinematic cutscene was so much awesome).
4) they need to rethink the JEDI/SITH training for Kylo and Rey. Better not repeat the ep4-6 style as that would be .. boring for this century. They should focus on Kylo training as a Sith and show how SITH training is like and Kylo need character development to show a change from wimpy to DarthVader level.
5) Luke should do a flash back on why he went missing.