Posted By:
MattHey Jason - interesting topic for discussion. If the list is going to be used as a checklist/registry idea, then I'd suggest one of the criterion being that each card needs to have at least 5 or 10 known examples so that it should be somewhat possible to chase the set.
If the list is to be more of a "most important" list such as for a coffee table book, then obviously 1 of 1s are fair game - heck; even fake Doyle cards could be used. 
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