Please offer some advice.

If you are already playing on the same computer, the interest and tension decrease. You know where he is, and vice versa. It is better to play on M or S maps because there is more interest... You never know which enemy will jump out from the shadows. Again, when playing on the same computer, you know what castle he has, so build units against that castle. For example, if he is playing Necropolis and has built vampires, take dragon golems and golems so that the vampire doesn't drain your HP (when playing as Haven). In general, think!