Oops, forgot to add, really good game though :) I didn't notice the achievements and such at first, perhaps it should be clearer that players do indeed have long term goals to work towards.
What Spathi! There ain't no Spathi! I don't know what you're talking about :)
To be honest, they'd totally just run away instead of asking you to defend anything.
Wow, this game has just proven that you can in fact get a dead bloody boring game if you ignore the game and concentrate solely on progression mechanics.