It is stat that is influenced by your relation to the SK, the count of the Doomsday count, and others. If it gets high enough you will start getting thralls in your cities. Think of them as rebels. The will costs you logistics point. You can raise hope - for example by using a city enchantment, which will lower the number of thralls.

I have no answer for this.

Top bar how well they like you - these points are gained by performing quest for them. 

Bottom bar - how well they like the SK. Performing a quest for another minor that hurts them (for example a dwarf quest to go and kill a bunch of Icelords - Dwarfs will like you, ice lords will hate you for completing the quest) will also raise this.

If the top bar fills up they ally with you, if the bottom bar fills up they ally with the SK.

Send a pioneer to the output, and once she on top of it you can upgrade the output.

It is in the log report (first one, directly under the overview header)

You get more recipes from quest, building libraries (and its successors: Jeweler, Scribe, Alchemist), souvereign skills, and other things (sometimes from winning a battle). Also you can enchant things like armour once you unlock the forge (either by souvereign skill 'Enchanted Forge' or by building the 'Order of the Forge').

Most recipe material are gained randomly, but there are a number that have preset conditions for obtaining them - Ogre blood from killing ogres, Wolf pelt from killing wolves, etc.