Yes, just as we choose which traditions to honor - what day to worship on, which days to hold sacred (Paul talked about some of this, see below).
did Paul suggest that each is to determine his/her own doctrine?
I have seen that thought before, never really understood it. He did almost say it in Romans 5:14 (One man esteemeth one day above another: another esteemeth every day alike. Let every man be fully persuaded in his own mind.). But I don't think he meant 'doctrine'. There is only 1 way to heaven (that whole 'died for my sins' thing, and 'there is no other name', 'ye must be born again' - that kinda stuff). But outside of that, we are all individuals. We have the same 'high-level' mission, but that is worked out in different ways. Some are missionaries, some are translators, some lead in worship, some in study & counseling, some are givers.
Or am I completely missing your point?
I think my point is different than yours concerning Paul's letter here. He certainly explains his doctrine, but he doesn't say, in effect "therefore whatever doctrine you explain is right also." Paul is speaking for the Church, not as one individual for himself only.
Another example is the Council of Jerusalem. Here they argue out doctrine, but they do not say: Ok, Peter you can have your own church and that doctrine, and James will have this one and that doctrine.
I.e., there is one doctrine and the Church has authority over what that doctrine and belief is.
Thanks very much for your reply.