ACE Pitcher is covered in the Game Manual. Ace goes longer. Interesting, the Manual also says you can set-up a six-man rotation. So try setting a LR as Rotation in games when your ACE is pitching. Keep in mind though, that your Ace may not be ready to pitch in the same spot in your next series.

As for the surprise starters, it has been covered earlier on this board. It happens because the game reads the away preferences locally on your PC, but then on the network it discovers that the guy is not eligible (tired or overused). I always have two browser sessions open when I play -- one for my team and one for the visitor (I have cable, so I don't know if this is a problem w/56K.) I ALWAYS check that the opposing manager is eligible. If not, the highest-rated eligible SP goes. I've known managers to send out the same SP every game just to screw-up the home guy.