I came across this really useful questionnaire that can be used as a sort of “litmus” test on possible new players in a campaign.
It can really help a GM in spotting any gaming pre-conceptions or ideologies that may conflict. Or even to put a spotlight on players who could be problematic or incompatible with your style.
I wish I had found this before I had begun my last (failed) campaign. It would have saved me some trouble: