I would fill up on granite and copper before I sell them, that way you can upgrade the roads, the more culture the better. Also if you are semi current on your storyline task I would wait for the sell dwarf portal quest to pop up before you sell it off, or you could end up like me, almost done with the orcs and my storyline tasks are stuck in the dwarf chapter...
Once you get the fairies going, depending on the amount of room you have available I would build 3-4 day farms and 4-5 night farms. These numbers worked well for me and I was never once tech locked