I wonder if virtue epistemology isn't particularly well-poised to solve the problem of prior probabilities. To a first approximation, you should adopt those prior probabilities that a virtuous agent would in a situation with no information. This is perhaps untenable, because maybe it's impossible to have a virtuous agent in a situation with no information (maybe one needs information to develop virtue). If so, then, to a second approximation, you should adopt those prior probabilities that are implicit in a virtuous agent's epistemic practices. Obviously a lot of work is needed to work out various details. And I suspect that the result will end up being kind-relative, like natural law epistemology (of which this might be a species).