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Yeah I feel that. I only know the concepts, but some user friendly stuff could go a long way in usability before you have to build something that's "to a t" perfect prediction market. Just start out with 4 or 5 buttons and take it from there: no clue, doubtful, neutral, positive, absolute
Then some concepts such as "double down" or "reverse order" if the user changes their mind or is more confident.