[AdmiralZhao]

1) I think that as you play more you will see that the micromanagement of mortal troops becomes progressively less important as a game goes on. Except for the indie expansion phase, the magical aspects of combat tend to dominate the battle. So by the time you have lots of troops and commanders, you won't have to worry about every last heavy infantry since you will be worrying about things like Shadow Blast, Darkness, and Army of Gold. Of course this introduces all sorts of the magical micromanagement problems, but that is at least a different can of worms.

2) A simple way to get this effect is to put your fast troops behind a wall of slow troops. In practice, I find that my armies have only one or two types of troops, which makes it fairly simple to have everyone arrive where they need to on time.