I agree all your points are valid ones, and probably addressing all of them is an impossibility, but all of that might be considered overly critical. An article like this, I think the only way it could meet the standards you've just set forth (which, theoretically, are all standards wikipedia is supposed to set forth) would be to completely neuter the article the way the List of Internet phenomena was recently. 
The MAIN problem is the one you raised about subjectivity. I don't believe there's any single standard that could truly be used to qualify what is an "unusual death", certainly not across the board for all types of death, and certainly not one which would be sourcable. I think, even above Original Research, it can be understood that the circumstances surrounding the demise of someone like, say, Michael Malloy, it can be understood that the vast majority of people would have no problem qualifying it as "unusual". But, reasonable expectation for popular agreement is not a consistent standard. So I simply do not know how to solve this particular problem.
If I were being completely objective, I would say all of your points raised are totally valid, and satisfactorily answering all of them is an impossibility, which would mean the article should be considered for deletion. But, subjectively, I like the article and feel it does serve a purpose, and if there is a way of answering any of your points, I'd like to try.