No, she didn't have her brain and spine removed, nor did her motivation change. Everything in this film was building off of plot threads lain down in TFA, including the shitty romance stuff with Kylo
No, it didn't. In TFA, Finn learned to fight. Here, he learned what to fight for. He had his own plotline which was given nearly as much focus as Rey and Poe's. It's hardly a sidestory.Finn got his entire growth from the third act of TFA ignored so he could be punished for caring about Rey, then shoved into an ancillary side-story that tried to limit him to only being a Resistance foot soldier with a boring girlfriend, in a subplot that basically crammed every non-white actor into it so they could all screw up for not blindly obeying the badly written white commander.