FSU is not a top 4 team without their QB. It makes a difference. How many of these playoff teams do you think they are better than or would be favored over. I don't think they beat them even with their #1 QB playing. But like you said it is subjective.
In what year were the 4 best teams ever in the CFP? Tough to say, because it is purely subjective, but I would be willing to bet that if you go back through the history, there was always at least one team that in hindsight did not belong.
My view is that FSU earned the right to compete through their regular season (which you claim will become meaningless in the 12 team playoff - I disagree there also, btw) and conference championship. The committee agreed, btw, until the final weekend.
Addendum: After the Tennessee game today, is Michigan one of the best 4? The Wolverines had 213 yards of offense against this Iowa defense. See, it is all just subjective.