Resources

Dilithium

Dyson Sphere Battlezone (Ground): 2,640 completing the 4 missions. 960 dilithium for each T-Rex killed.
Turn Over Confiscated Contraband DOFF Mission: 2,000 every 4 hours. (click link for more info)
Path of the Warrior Mission Set (KDF Only): Each of the Sortie Sets awards 960, and the Path of the Warrior bonus rewards 2400, for a total of 4320 dilithium for about 30 minutes of space combat.
Elite Special Task Force (STF) Missions: 960 Per Elite STF (should be able to knock out 3 in 30-45 mins)
Asteroid Mining: 125-1000 dilithium in about 15 mins. (1500 max during event)
Fleet Asteroid Mining: ???

Foundry Missions: Find a foundry mission with the word, “Farm” or “loot” in the title. These missions make it easy for you to kill a lot of enemies very quickly, which gives you a lot of quick drops that you can sell at the vendor for money. Most level 50 toons get 300,000 to 500,000 EC from doing this. It takes about 15 mins.
During the Officer Reports event, you will also receive bonus Dilithium, provided you run a foundry mission that qualifies.

Mirror Universe Incursion Event: If you need Skill Points, or to level a toon, this is really the best way to do it. This event usually runs for an hour once a day, and gives TONS of XP.
Defera Hard Missions and Crafting Missions: Given that it only takes 15 mins to run through these mission, you get some significant Skill points in a very short period of time.

Defera Hard Missions: Running the four hard missions gets you 240 fleet marks. (260 during bonus marks)
No Win Scenario: The amount of fleet marks goes up the longer you can run, for a total of over 400 fleet marks for wave 10, which takes about 15 minutes. (assuming you can make it that far)
Fleet Defense: These reward 40-60 fleet marks for about 10-15 minutes of work.

If you run Defera, you probably have a lot of Nanopower Capacitors, Cybernetic Armatures, and Fibro-Neural Interface Cabling from drops. You can use those items to craft items at the Researcher near the Mail Station. The quests are: Agile Assembler, Deft Designer, and Prolific Producer. The quests give a ton of skill points, and crafting the items gives you general crafting XP. This is probably the least expensive way to level up your crafting.