Getting Strategic is not that hard, the level is more a 'check' that you are doing the basic things right. It's a straight out 1v1 battle with the AI. This being an AI, the weaknesses is also know.
1. AI don't think ahead. Only the current turn matters for them.
2. Prod 2.0 (the SP AI) is very happy in expanding. So if you meet early, you can almost always safely attack it.
3. The AI, don't check turn 0 standing. It will enter bonuses with wastelands (the 10s). While you, definitely should be smarter than that. Use history, during the game.
And perhaps most important, make sure you expand well. What bonuses are you picking? Are you attacking neutral 2's with more than 3? Expand fast and efficient. Getting early income is extremely important. After turn 2, you should probably have 12 or more income at least.
Quick Link: https://www.warlight.net/SinglePlayer?Level=56
EDIT: Also, I strongly recommend checking out MP games. Particularly the 1v1 -Autogame. You will be able to learn by playing fast that way.
Edited 5/31/2017 10:36:13