What is the best way to shift when in this mode? Hold the gas? Let off? Shift at redline? shift a 1k rpm before?

This is in regards to "spirited" driving. My first gear keeps hitting the rev limiter even though I shift before I come onto the redline.

 

you need to shift before it redlines or the limiter will kick in
1st is not your power gear, get moving then into 2nd
read owner book for speed limits on up and down shift-
Stay on the throttle all the time- its an automatic- you are just triggering a signal

 

I don't know if it's just me, but the sports shifting starts to shift faster over time as you break in the car. I've noticed that my shifts are shifting much faster than when it was new.

 

the parts do need to mesh together with time and the cars computer learns your driving style and adapts shift points to you

Have you read the owner book- lots of important info in there about traction control- brakes etc

If you want super fast revving- which gets you on the torque band where the power is - install a lightweight crankshaft pulley...its a different car afterwards.
8 pounds on the end of the crank stock- 2 pounds after!!! vroooom vrooom