Here's some from me...
1) Fortify your forward warp points well enough, and your enemy will make a new one behind you for certain.
2) When you have secured a system, don't forget to tell the enemy.
3) Alliances are essential, they give your enemies someone else to shoot at.
4) War is based on deception...deceive the enemy, not yourself.
-and Last, but not least-
5) No matter how well assembled, no formation/strategy survives first contact with your enemy (particularly when using "strategic" combat
).