How "imperfect" does a party have to be before that becomes a waste of time though? My local org disagreed with me on every important issue last time I spoke to them, and joining them would do nothing but have me get into pointless arguments with "Weekend Communists"

I'm not saying I'm holding out for a "perfect" party here, but I feel like the line should be drawn with this: "Can I do more good work within this organisation than I can outside of it?" Having access to a properly organised group, even an imperfect one, enables an individual to do a lot more good in the world than if they were acting alone, but spending time in a party that does nothing of value will only waste your own time.