I really agree with both of you - it is a balancing game and something I have considered doing. If you wanted to test it out, I would drop fatigue in the 60-65 range and see how that looks/feels over a few games. I would also get a feel about how quickly players get subbed (i.e. if it takes a RB with typical stamina 10+ carries in a row to get subbed, it is too low).
Side note: I am back to being hooked on NCAA14 for the time being. However, I will still be checking this thread out. If anyone would like to try out the fatigue adjustments and maybe even give RTP at 53 a shot (my next pondered adjustment to help slow down the pass rush a tad), that would be terrific - just post your findings in the thread....