Romans 6 - What Shall We Say Then?

At the end of chapter 5 Paul leaves us with the idea that where "sin increases, grace increases all the more," which naturally leads to the question of whether or not sin can be desirable, in an effort to make grace abound.  Paul deals with this immediately and decisively at the beginning of chapter 6.

Shall we go on sinning so that grace may increase?  By no means! (v. 1-2)

Our old self was crucified with Christ (v. 6) so that the body of sin is dead.  We have been set free from sin (v. 7).  We must not offer our bodies to wickedness, but rather as servants to God and slaves to righteousness (v.13).  We are reminded that sin = death (v. 23).  

OK, so sin is bad and never to be embraced.  Got it.  Simple as that seems, why does it get more complicated as we live out our lives?  Why does sin hold appeal?  How do we become slaves of righteousness?  I'll be reading the next few chapters with those questions in mind.