The more I think about Finns character the more I have a problem with him. And it's got nothing to do with race or the fact that he's probably not gonna be a Jedi.
Finn is a storm trooper raised from infancy. At the very least 20 years of mental conditioning. Homie doesn't even have a name. Only knows what the first order has trained into him. A brain washed soldier. All of a sudden for the first time ever a storm trooper randomly gains a conscience about what they do. Deus ex machina IMO. That just doesn't happen. Not like that.
This is a supposed soldier who was raised to kill. Not only does he defect but has zero issues with killing his former allies. Dudes he legitimately grew up with. It goes from in the very beginning him being shook that his fellow storm trooper got murked next to him ( honestly looked like it could've been a friend of his) to killing storm troopers without batting an eye.
Another problem I have with Finn is his personality. For a storm trooper trained and conditioned from birth to kill he has a pretty plucky and fun personality. Just doesn't fit with the facts of what he is. This dude is someone who should be struggling with the idea of what fun or free will is. Not someone cracking jokes every scene. Unless I got the wrong impression of the first order, they don't seem like a group that foster an environment conducive to soldiers with fun loving personalities. The concept of being free should've even been ground breaking to him.
Honestly I like Finn. I thought he was funny and tried his best but when I consider he is a storm trooper who randomly defected nothing fits. His personality nor his actions fits that of a child raised to be a soldier by an evil space nazi like terror group. That's just my opinion