It really depends upon the coach. I'm not patient enough for DI-AA, I don't like DIII because my favorite level is DIA & DII so I try to get there as soon as possible.
There are so many variables to winning a NC. DIAA through DIII have vision so you have to build up vision to get the best players to compete and eventually win. DIA allows everyone to see so you get a lot of coaches who will just go after talent.
Usually the coaches with the best combination of planning and execution with regards to recruiting, game planning and strategy win the NC.
For me I feel it is DIA. For the amount of coaching talent as well as the varying levels of success needed to coach, recruit and win. DII was easier for me, it was my favorite level for a long time and even when I won my 2 NC's in Wilkinson, I didn't game plan for any specific coaches, I had certain generic plans in place based upon what coaches tendencies were and when I played them I looked at their team stats and put in the game plan based on that.