Lumen
You have so many different things, and this discussion is getting so buried, it's difficult to pick one item.

I'll just say, that in my own view, unless we are honest and deal with our official Church Biblical teaching, we are straying from truth we know, and become irrelevant. Scripture Studies and Theology have to work in tandem. 

Yes, we are challenged to re-examine our theological assumptions once we accept that the Genesis Creation stories are given by God as a 'myth' literary form. 

- What we call 'fallen' nature, is simply 'human' nature.
- Just possibly God creates humans through an evolutionary process.
- Each person is responsible only for their own sins. We don't 'inherit' guilt, even if we do inherit the world our ancestors gave to us, and our children will inherit the world we pass on to them.
- Everyone is 'conceived' and born without 'original sin' because there was none
- Jesus redeems & saves us from our own sins. 

Much more, but that's a start.