I'm currently in Woodelves, and I've given up my full speed ahead strategy. I've just joined an FS that gets all 10 chests (lots of KP Instants) and lots of AW trading loops. So I'm focusing mainly on AWs for the time being. But Dwarves and Fairies? I dump KP as long as I can. But as soon as I'm really stuck, stop KP entirely. ONLY when my Portal and Buildings are sufficiently upgraded to whatever level I want, Level 4 Granites and 2 and 3 Copper Foundries for the Dwarven chapter, would I resume. That way you're only really stuck once.
I agree with maxing on Copper. You only need 5 Foundries at Level 3, maybe 4. Maybe 4 Foundries if they're all maxed. Lots of Granite. I think 20 might be a bit much, but hey, if you've got the space...