Had some good discussions on Sunday regarding some aspects of Rom 2. Some that stood out to me and would be willing to discuss more are the following.
#1 To what degree can you trust your conscience? (Rom 2:15)
#2 Can one be "saved" even if they've committed no offense? (Rom 2:7,10)
#3 Do we over-emphasize grace? (Rom 2:5-11)
To #1 -- My short answer on this is... see Rom 14. The biblical example of varying conscience regarding meat and special days declares pretty clearly that our conscience, even among Christians, is not objective, consistent and reliable. Not that we should ignore our conscience for that is its own sin (Rom 14:23) but we need to submit and shape our conscience to fit truth rather than fit truth to the whims of our conscience.
To #2 -- Yes, because the judgment we ultimately face is a judgment against mankind as a whole, not just us as individuals. Thus, even if we could (for sake of discussion) live an entire lifetime free of personal sin we are nevertheless 'sinners" positionally by nature and in need of salvation.
To #3 -- In the context of "getting saved" (justification) I think it's impossible to over-emphasize grace since salvation is by no other means than grace through faith. (Eph 2:8,9) It's often confusing in-fact to discuss sanctification in the context of justification because there's a tendency to blur the distinction as do John MacArthur, Ray Comfort, and others who espouse Lordship Salvation.
However, In the context of "living saved" (sanctification) grace CAN be over-emphasized to the point of fostering an antinomian attitude which is just as wrong as legalism. (Rom 6).