I’d say the film is great. The argument, however, is broken…or incomplete, or just not there.
Are you speaking of finishing the story in a Dramatica storyform sense? I have a hard time seeing how that could happen without a proper Dramatica MC in place in IW. Seems like it would have to place the entirety of IW into Act 1 of its argument. I’m hoping the next one will end up having a complete argument between Captain Marvel and Thanos that maybe uses IW as backstory or something.