A four team playoff allows various teams to assert their contendability for a title bid. This principle is exemplified well in the 2011 BCS Championship in which LSU played Alabama. In the same year, Oklahoma State, who was ranked third in the final BCS polls, with a viable claim on the National Championship, was entirely neglected in contention for the title. A four team playoff would have allowed Oklahoma State a shot at the title, via playing Alabama in a national semifinal.
I think college football would highly benefit if there were playoffs. NFL recruiters would have a better understanding as to how college players perform under pressure and who is really the best team and player. Though there would be more injuries, playoffs would generate more money for local economies and help underdogs get discovered.
Many people would disagree with me but I have some facts that support my opinion. Like if college football had playoffs the season would extend at least a another month and that will interfere with college exams. Also players are more likely to get hurt because the season is extended.
College football is good but if the thirteen week season runs long then there will be no time for the players to study so they get injured more frequently in games. The players are sometimes forced to get back in the game if they're injured or not either way they have to get back in.