Looks like everyone writes his/her thoughts about the mission and his/her rules here. Here are mine:
Personal rules:
- Hard skill
- All roads connected
- No slums
- No salary, no gifts
- 100 prosperity
- No unfunctional buildings
- Good culture (where possible)
- Stable city
- No 1x1 houses
- All houses full (in most missions)
About the mission: After I have beaten the game on normal difficulty, I restarted it on hard to play the alternate missions I haven't done yet. Selima is very easy, the only thing you should worry about is getting luxory goods, because the trade route is frequently under siege. And without luxories there are no manors. I think I should have built more manors to reduce unemployement.