There are many ethical viewpoints for life. A few of them have serious flaws from a Christian perspective.
Consequentialism is a view that there is some common good which should be values. What is ethical is maximizing this common good.
A major flaw of the system of consequentialism is that it can be just or ethical to run over or mistreat others to obtain a result. This end justifies the means worldview has serious concerns from a Christian perspective.
You cannot condemn consequentialism absolutely but it is concerning especially when it is oneself who determines what will cause the perceived good. Since the heart is evil and crooked a system where ends justifies means is very suspect to cause unethical behavior.
Another system of thought is that which is described as everyone is permitted to do anything the please so long as it does not affect oneself negatively. The flaw of this view is that what negatively affects oneself is subjective.
One will often find this as a critique of religion as religion is a nuisance to oneself. Often ironically the same people holding the critique are also a nuisance to religion...
Ethics as all is permitted except what bothers oneself is actually a fairly incoherent system since what bothers everyone is different. If we all agree on this ethic there is no use to it since we will all disagree on what is bothersome.
There are too many ethics to really discuss, but Christian ethics has a distinctly pleasant element - simplicity. Really Christian ethics can be boiled down into loving God and loving our neighbor and correctly understood our neighbor includes everyone.
The bible gives a lot of help on this principle of what love is since people have by nature fallen views of this concept. But the reality is the biblical framework is simply on the basis of love and the ethical teaching is simply to set fallen minds set correctly on what is or is not loving.