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Better tuning than what Roush did? Not worth the redo. You can swap pullies and get a dyno tune (or something from VPM), but it will just put you closer to the limits on the rest of the motor.
Congrats on the S3. I think the stock bottom end is maxed out (or close to it) at 565. You could try tune, smaller pulley, headers, etc., but it's a significant risk.