Its not an issue of how fast they can recover, its an issue of how effective will they be when they are pitching tired. Your 80/80 Ace might be a worse pitcher than your 60/60 reliever once he gets into the 8th and 9th inning.
In other words, your pitch count should reflect how long your starter can pitch effectively, not how long he can pitch and still recover for his next start.
Start with the recommended settings and adjust upward or downward through time based on your experience and observation.