I would want to build something of my own. Something that was mine. Its not hard to win at Florida, Georgia, Alabama, etc. Is it easy to win NCs? No. Thats not easy anywhere, but to win at those places isn't tough.
You look at FSU before Bobby Bowden. He has built a legacy that very few have had or ever will have. He built that program from almost exactly what MSU is. Granted he had a hot bed of talent just waiting to be discovered, but he still made them a perennial power house from a perennial door mat.
Lets say I was a young and up and coming coach and took a new job at Ole Miss, Kentucky, South Carolina, Iowa, Kansas, Texas A & M, hell even Miss. Southern, etc (i leave out state so I'm not biased). If I had the opportunity to build up one of those programs to an FSU, LSU, Georgia, etc., I'd pick staying anyday over leaving. The schools I mentioned are all schools where a coach could have success (MSU included). Now success would be much harder earned for many reasons I don't care to get into but thats part of the reason I'd pick those over a gimme (so to speak).
Here's the question you have to ask yourself if you were a coach. Would it be more rewarding to consistently win 7 to 9 games at MSU (occassionally winning 10, 11, or 12 and occassionally only winning 4 or 5) or to possibly win a NC at a Florida, LSU, Texas? For me it would be at an MSU or one of the others I mentioned.
I understand most people wouldn't look at it that way though.