I'm not a Christian anymore, but I have a couple of annoyances from when I was a devout Christian.
My first annoyance...
I was severely abused and perpetually bullied while I was growing up. In spite of the living hell that I was literally trapped in, I still had an unwavering faith in the Christian God when I was a child up until my early teenage years. In fact, I'd constantly pray and ask God to save me from all the abuse and bullying that I was forced to endure, but all my sincere prayers went unanswered, and I endured the abuse and bullying for 13 1/2 years. It didn't stop until I took the matter into my own hands when I was 18. I stood up against my abusive brother and mother because I fought back against them. I threatened to call the police on my brother if he ever hit me again. I blatantly told him that there's not a damn thing mom and dad can do about it. He looked at my dad and my dad said, "She's right!" My brother never laid a hand on me again, and my mom never hit me again, either. I scared the hell out of them.
I said all that to say this... I've shared my story with Christians in the past and the typical responses have been: (1) "You obviously didn't have enough faith that God would help you," (2) "You must have had sin in your life, so God decided not to answer your prayers," (3) "God allowed you to suffer the abuse, so you could help other people who also suffer from abuse," and my personal favorite (sarcasm) came from an evangelical pastor I had counseled with, "You're obviously a cursed soul and God is punishing you for the sins of your biological parents." He then proceeded to tell me that it's become obvious to him that God hates me. This is the same pastor who would stand behind the podium on Sunday mornings and tell the congregation that God sent his son to die for them because he loves them. He also told them that God is their heavenly father, and he will always take care of them and protect them. And I'm sitting there in the pew listening to his sermon, thinking, "What could I have possibly done to make God hate me?"
My second annoyance...
"You're not a 'real Christian' because you don't pray to God like you're supposed to," or "You don't believe [fill in the blank] like I do," or "You don't follow the right Christian doctrine," or "You voted Democratic, and all Democrats are anti-Christian," or "You don't support Trump." I've actually been griped out and accused of these last two accusations by evangelical Christians, who also accused me of being demon possessed because I voted for Joe Biden, and apparently, I'm going to hell because I voted for him.