The laser bolt was friggin sweet...then by the end of the film a person who found out she was Force Sensitive like 35 seconds ago was able to not only escape all of his guards but hold her own against him.
Meanwhile he kills his dad as a way for JJ to end that character AND show Kylo is all in trying to be the next Vader (which was an excellent way to accomplish both) only to have Rian turn him into a whiny child again in the next film. If Kylo had taken the next step I think I would like him better instead we had that stupid "connection" crap where he and Rey were stalking each other in their minds. He stopped wearing the mask, he stopped really being evil...and just kind of sucked. (for Obiwons Sake he was fooled by an Astral Projection that he watched "survive" like a thousand laser bolts) To use the prequels as an example...Kylo went from AOTC Anakin being told by Palpatine how great he is to become to ROTS Anakin whining about his lack of respect BACK to AOTC Anakin only the one with Padme on the stupid planet having their rom-com moment. There wasnt any real progression...just little things they did trying to make him look cool that fell flat on their face.
And that is where I think Rian dropped the ball. By making the "Empire 2.0" complete morons (which he did...they friggin fell for a fake phone call for Pete's Sake) he also had to dumb down the "NuRebellion" to make it work. Neither had a plan worth a ****, all of their strategies were stupid ("find the code breaker!" "CHASE THEM TIL THEY RUN OUT OF GAS!") and in the end it was obvious all it was meant to do was make the "NuRebellion" look outmatched like the original did even though they were a fully formed Alliance/Government in the last film. Meanwhile you have the Dark Lord and the "NuJedi" on a collision course...except they arent because they are also apparently Star Crossed lovers swooning. No wonder Luke did what he did he probably had migraines from all of the facepalms and said "Screw it I am out of here!"