I should preface some of my posts with I actually don't own the 7AT, I have had the chance to stumble upon certain reading material which I have shared & driven a built block TT 370z with 7AT.
Running cooler between a SC/TT will be the SC just because you are not trapping heat around the block to turn the turbine to create power, but remember a TT (or T) is going to be more efficient.
When I drove the TT I always did manual mode just because it was easier for me to correlate the boost v rpm v gear and make sure I was driving right, but that is just my brain which has driven manual only transmission (unless it is a rental car). I think without a
VB upgrade staying out of boost in the top few gears is wise just because of the strain it will put on them and cause early failure. Plus redline in 4th is easily in the mid 100 speed so that is probably pushing what most need.