Yeah, Finn is a terrible character. I initially thought he was okay because he was on a character arc. I figured he would start out as something (a bumbler and a stumbler and general coward), and hopefully end up as something else (preferably a cool Jedi). I was dead wrong. The character's only arc is to go from running away from the First Order to standing up to them with The Resistance. I was a lot more naive when I first saw The Force Awakens. I would probably see through that now, just like I realized relatively early on John Stewart would be essentially worthless in Snyder's Justice League run. I've been led along on a string too many times and had my time and investment wasted too many times. Eventually you start seeing it coming in the early stages. I tried to warn people, but they wouldn't listen to me
All that said, I think John Boyega is a brilliant and extremely charismatic actor and is the only saving grace of the Finn character.