GC leves and Regional leves have been improved a TON this latest patch. With food buff, I reliably got between a third to a half of my needed experience for next level per set of 4 leves, from level 10 to level 35ish.

Just set your homepoint to the camp you're exping in, or favorite the camp and set your homepoint in the camp's nation, and you can level at a pretty decent rate.