The best place for crystals and lifeforce seems to be the first gate at the Wasteland Final Sanctuary. Once you port in go down the small hill and you'll see a huge gathering of gnomes, upwards of 50+.
Alternatively if you aren't there yet, you can go back to the Everlight facility you were sneaking around in with the greens. Open one of the gnome gates, stand a good distance away from it and send your minions in to slaughter the gnomes as they come out. (note the gnomes will only come out in 4-6 gnome groups when you aren't near the gate entrance) Since it seems that they spawn infinitely then you can get as much as you want depending on your tolerance for grinding.
For gold you can go back to Nordberg and there will be 7-10 chests right in front of the gate. Everlight temple seems to be another good place to get large quantities of gold from the large concentration of chests.