Hello,

- Weekly reset is Monday. Don't know the exact time. Must be very early in the morning (in Germany). Possibly at midnight Sunday->Monday.

- The higher the mission difficulty the higher is the amount of fate. You can push that with different tarot cards (+x% overall reward)

- Simply play missions in the desired system. You can push that with tarot cards too (+x% overall reward and there's a tarot card especially for influence). And again: higher difficulty -> more influence. 

- You have to complete the cabal directives for cabal xp. But do yourself a favor and gather some members. Solo it's a pain in the a**.

- Every class has some sort of AoE Builds. Depends on the weapon/psyker ability used.

- Same for Single DPS.

- Don't know your current level but maybe your build is simply not strong enough for some of the Intel mods yet (No crits, all enemies are heavy armoured or 60% more damage for enemies and stuff like that). If you're still beneath lvl70 I would recommend doing normal system missions around your current level from the missions overview. Intel missions and void crusades are more like "endgame stuff". 

Focus on one or two skills from your current weapon when it comes to choice of passives (ranged or melee dmg, physical or heat and so on). Maybe some points in health/armour. There're many useful "main"-nodes in the passive trees that can be reached with 2-3 skill points. 

Builds change a lot when you go full relic/aerotech later. Before that almost everything should work out somehow.

- Just salvage everything you don't need/use. Credits shouldn't be a problem so don't sell your equipment. And again save your materials for endgame. You'll need A TON of it.

- There's a tarot card for a better chance finding blueprints. Or buy it at the trader/Ordos. You will get most of the purple blueprints just by playing the game.