I watch Catholic Mass when I can't get to my church and it is fine. I find the Catholic Mass very professionally conducted. I'm not a fan for back street religion like some red letter and evangelic, etc.
I've been to the Catholic church and their members are mostly good people which is a reflection of the fruit of that church. Catholic people are doing just fine so I doubt there is anything regarding the issues you speak of.
Demonic possession might be an issue as I see it with communicating with the dead, so you might have a point there. I only pray to The Father in the name of Jesus the Christ. I'm not a fan of praying to anyone but God. And I have been visited by Angels and they have proven to me that they are Angels of God.
Anyone that has a cross around their neck could be guilty of idolatry in my opinion. I don't wear or worship the cross as it is a sign of the traitor against Jesus and desiring him to be killed from the earth so we can have earthly leadership instead. While he had to die, it wasn't the crucifixion that ultimately caused his sacrifice. As he instructed us, he alone had power to lay down his life and take it up again (John 10:18). So why worship the cross that had no effect on his sacrifice but physical and emotional suffering and humiliation towards Jesus? Hmmm, that should stir up some responses
There are abuse allegations in any church as well as many churches hide abuse allegations. The bigger the church the more allegations that church will have. Boy scouts got their dose recently and it is not a demonic church either. The problem is that the predators infiltrate the organizations that they benefit from, which is church and child care, Boy and Girl scouts, etc.