Regarding the Tear of Ash: it was designed so that it would be difficult and, often, not worthwhile to reach. It provides a huge advantage in itself, and it can also be turned in for a quest to receive a dozen phoenixes. This is too strong an advantage at any stage of the game, so trying to capture Ash will require significant sacrifices in macro-game play – control of the map: giving up the center, mines, and cities. Let's just say it's a "do-or-die" situation.