AND each of the marauders died protecting Harry. James died literally protecting him, Sirius died to go save him, Peter died allowing him to escape the prison, and Lupin died fighting with him at the Battle of Hogwarts. All of them died for Harry.
This is funny, but I always got the implication from the books that there had been people trying out for Seeker, but none of them had been very good. So McGonagall stepped in because she loves her House team.