Edit the campaign.xml in the content folder, 5th line (just in notepad nowrap, or line 6 with a reasonable window) is VictoryCouncilFavor="val|val|val" with each value corresponding to each tier of success in the missions, and just after is extraFavorForDifficulty which is the additive modifier for the mission difficulties I think.
A restart/new campaign also seems to skip the tutorial mission and give you the victory/favor for it.
How to use this cheat table?
Install Cheat Engine
Double-click the .CT file in order to open it.
Click the PC icon in Cheat Engine in order to select the game process.
Keep the list.
Activate the trainer options by checking boxes or setting values from 0 to 1