You sound like you are confused, but I can see through the ignorance to the rebellious heart.
Perhaps you have an example of how Christians are "trying to run people's lives"?
As to "slavery and genocide" being "okay", it depends on who is directing it. Man does it apart from God- bad. Israel did it at the command of God- good. God made us, so He can do with us as He pleases, and while He does not desire the death of the wicked, He allows each to decide their own fate. So, if you don't like being a slave, or on the wrong end of genocide, get your heart right with the Lord.
Fun facts- God sent Israel into a number of small nations to eradicate them because of the sin of those living there. The things they did to each other was put to an end, and God fulfilled His promise to Abraham when it came to his descendants inheriting the land. And much of slavery as described in the Bible is not the type of slavery that took place in America. Sure, some of it was, but it was those same nations being enslaved because of their sin against God's people.
None of those commands are for the Church Age, and I know of no Christian that considers any of it "ok" in the sense of enjoying that it happened. It is only "ok" with us because God determined it to be. God, being God, is considerably more intelligent, just, and loving than you are- imma take His Word on it.
Still, it is fabulous that you have some sense of something being wrong, in spite of the fact that apart from God, there is no such thing as "right and wrong", regardless of how atheists claim to the contrary. It is just your opinion that it is wrong, and in a few short years, your opinion will die with you; your opinion is worthless. However, knowing that it is wrong means you have a conscience, therefore you are without excuse:
John 9:41
Jesus said to them, “If you were blind, you would have no guilt;
But now that you say, ‘We see,’ your guilt remains.