But I feel like some parts were unnecessary, for example Canto Bight, which was just filler. It's one thing to not have something, but it has to be held by something as good, or better. Finn, one of the main characters, was wasted. We could've seen more about the First Order, and how Finn is still torn between the First Order, Resistance and living a neutral, quiet life in a more detailed, and focused way. But we got a pointless scene which served nothing. We don't know much more than the characters we got. Heck, even the character which was introduced, the code slicer guy, was wasted. I would've loved to see Finn play a major part, tying to his backstory in a more unique way. What they did on Canto Bight could be done by anyone else, really, and it wouldn't make much of a difference instead "they rescued some horses so yeah, worth it.".
And that admiral who replaced Leia for a bit wasn't needed. We could've had Ackbar, or a general who actual didn't make me cringe about "we have a plan, perhaps, but not really, perhaps, and if we had a plan, we still wouldn't tell or show you, perhaps.". That made no sense, whatsoever. At least she would've given a briefing on what to do. If she told everyone what will happen, it wouldn't have caused the mutiny, done by Po. It made no sense for her to hide the plan if it would only cause distress. And if she didn't have a plan, gather the officers and make a plan. But no, we got avoidable, pointless conflict.
One of the worst sins, if not the worst sin, the movie did was not do anything with Snoke. They tried so hard to not do what fan theories expected to where they didn't bother to explain Snoke. He ended up being pointless, and if, in the next movie, Snoke isn't explained, that would ruin the entire trilogy for me, though I would still kinda like Force Awakens, since Force Awakens is pretty cool, not gonna lie. But Last Jedi did nothing to show, or even tell about what Snoke is. Or who Snoke is? Or why? And this sort of goes for Rey, who is at this point very close to being, if not is a Mary Sue. She had little to no training and is able to lift up boulders without failure.
And I do kinda like what they did to Luke, I think him being in exile and jaded is a good idea, but his finale should've been better. I know I seem like a "fanservice or die" person but it wasted so much of what could've happened, which is why the movie fails. It replaces the extremely cool stuff which fans wanted with kinda cool stuff.