Thanks for getting this started, Daniel (and great talking in Prague).
I would imagine there will be many reputation systems long-term, and trying to standardize too much will be futile. But hopefully we can agree on a few baselines that guide development across the board. The main thing that I think is critical and oft-overlooked is that reputation must be contextual. Contexts can be specific (a particular marketplace dapp) or very broad (you followed through on your promise to repay credit). But trying to ‘use’ a reputation outside the context it was generated will quickly make it either useless or dangerous.
Norms vary too much across contexts for ‘universal’ reputations of any kind. Even if we subdivide from a ‘general reputation score’ into traits, skills, etc. the context still matters. What qualifies as ‘open’ in one society or community or marketplace will be very different than in others. There’s a large amount of data on this. It also is how reputation works in the physical world, which we often don’t learn from enough as we try to recreate digital systems.