Moradin, there are very good reasons why we don't need, or want, to ally with Springdale, retirement home for failed warriors. Springdale has proved itself to be totally untrustworthy in the past when dealing with real cities. I recall when spheres of influence were first introduced you made treaties with Thakria, Parrius and Mercinae over the boundries you would form with villages... If Parrius' or Mercinae's government are stupid enough to believe you won't disregard anything they have done for you in the past if it's in your best interests, then more fool them.
Remember, as long as Thakria has people like myself or Xandamere, diplomacy isn't needed.