Christianity isn't going to the cross at first and moving on from there to deeper things. It is going to the cross and going deeper into it.
I was flipping channels last night in a 20-minute attempt to clear my brain before bedtime and ran across Carl Sagan's Contact with Jodie Foster. In the scene I'm describing, they're at the Mall in DC where she and the pseudopriest Matthew McConaughey are talking about her reasons for going. Right before the romantic kiss and the mutual confusion that ensues, this conversation happens (slightly paraphrased).
MM: Why do you want to go? You, not humanity, but you?
JF: Ever since I was a little I wanted to know if there was more.
MM: Why would you risk losing everything? Is it really worth your life?
JF: To find out our purpose in the universe? I think it's absolutely worth a life.
That got me thinking about a person who gave His life. In that death we find salvation through forgiveness and the imputation of righteousness. But we also find our God-glorifying purpose on display. And there's love on display, powerfully portrayed in the sacrifice. Then there's victory over the spiritual forces of darkness. And reconciliation to God and one another. And the promised healing whereby He will set the whole world right again. And on and on we could go.
So much happened at the cross. So much is revealed. So don't fall for the mindset that the cross is the beginning and then from there you move on. The cross is like the spring in the middle of the City of God - the place life begins and is sustained. Move deeper into it, not away from it.