Yup! Once again, Finn begins the film as a coward. Once again, his female co-lead in the film knocks him on his ass. Once again, Finn is tased. Instead of being a slave to the First Order, Finn is now a slave to the Resistance. Until he finally becomes loyal to the Resistance, Finn's only real motivations are cowardice and his obsession with Rey and her safety.
His whole side mission with deactivating the tracking device was pointless because he failed and because it could've been avoided had Holdo told Poe her plans. In fact, it's even worse because DJ's betrayal meant more Resistance people died. His fight with Phasma was, more or less, a rehash of his fight with TR-8R. Finn starts off aggressive and badass, matches weapons for a moment, moves backwards as his opponent gets the upper hand and finally gets knocked down/out. This time, instead of needing a white savior, they rehash Finn cheaply stabbing that stormtrooper in TFA by having him hit Phasma while she wasn't paying attention. Not a satisfying victory.
Near the end, Rose stops Finn from sacrificing himself. Again, not satisfying. It's made even worse because the shield door blast didn't kill anyone, and Luke was used as a distraction. Rose kissing him felt forced, and it feels like she's largely there to keep Finn from romancing the white girl.
Finn didn't explore his backstory as a former slave to the First Order. He had no real interest in trying to locate his long lost family. He suddenly knows how to pilot that ship on Crait... kind of? Yeah, heh. As soon as it crashed in the trailer, I was like, "Yup. That's a Finn move!"
The dude is just a glorified grunt now, not really distinguishable from the regular Resistance members. He went from being a main character with untapped potential to an annoying distraction from Rey and Kylo Ren's story. Even Poe is being groomed to be the new Resistance leader. What purpose does Finn serve now? Even the porgs are funnier than him.
Since Disney is so fond of their "one negro per Star Wars film" rule, I say just kill Finn off in a decently heroic manner before immediately replacing him with Lando. Opening scene, anyone?
