I wouldn't call it muscling her aside, I'd say "just as much right through our own efforts". There are many biblical examples, but the thief on the cross is one that gives many hope. He's been a criminal--so much so that he was being crucified, but he did the only things that God says we have to do to be justified in His eyes and get into heaven: repent of what you've done, and believe that Jesus is Who He says He is and that He did what He said He did. So yes, if you killed everyone on the planet, and then repented of it and accepted Christ as your Lord and Savior, you're in. So God says, at least--and I believe Him.
Though it sounds very easy to "be golden", our nature isn't set up for it. That's residue from the Fall of Adam and Eve.
No one's saying that helping people isn't pleasing to God. No one's saying that we need to live a hedonistic, narcissistic life because we're covered by Jesus. Romans 5 and 6 are tough chapters (heck, Romans is a tough book) to understand, and implications of the teaching are far-reaching. Obviously I recommend reading it instead of taking my word for things, but the short answer for your "why go to church?" question is community. Church is the body of believers, not a building you go to on Sunday morning. It's a way to be encouraged, taught, held accountable, exhorted. It's an outlet for you to teach, help, serve, grow. There are people there you need, and people who need you. That's a crazy and great thing about how God's ways aren't ours: that He brings together people whose sole similar characteristic is their devotion to and worship of Him, and that so many blessings come from that.