Tactics in BATTLES

I hardly play online at all. As for playing against the computer, it seems to me that the tactics of casting Meteor Shower and repeatedly using Escape, sending a "Matrosov" to the enemy gates, practically negate the computer's already slim chances of winning... In general, I try to cast Restoration as little as possible and practically never cast Portal, Flight, or Dimension Door. Why, after making an elegant move with a hero and one Phoenix, and wiping out the entire enemy army with magic, practically without any suspense, end the map completion?... That's not very sporting :)