Sprint: you want speed and power, mainly speed. Guts and stamina are out the window. Get at least 300 wit. Run 4spd, 2pwr cards. Or 3spd, 2 power, fine motion. Power is great in general for late surfers and end closers.
Mile: exact same as sprint, you’ll get enough stamina to win races by just naturally training other stats, or training stamina when there are lots of characters at that facility.
Medium: run 3spd, 1 sta (super creek), 1pwr, 1 int (fine motion). Or replace the int for another speed. You’ll want around 400-500 sta and the swinging maestro skill from super creek. Power is less important but still necessary at this point.
Long: 2sta, 3spd, 1int. You want 500-800 stamina as well as swinging maestro + at least 1 other blue stamina skill. Power is more or less unimportant unless you are training gold ship who is an end closer.
No one cares about Dirt