Eschatology does matter! One's eschatology defines his view of the nature of the Kingdom of God.

A post-millennialist, for example, is more likely to view the kingdom in a physical and political sense, achieving it's apex in a great "Jewish-style golden age" before the Lord's return.

An amillennialist sees the kingdom as spiritual sense, as the Lord described it, "My kingdom is not of this world." The Lord's return finds a Church gloriously purified through trial, perhaps driven underground and almost out of sight by persecution. The true remnant of the Elect, having refused the kool-aid of compromise, they have triumphed spiritually. The number of the Elect is counted throughout history rather than "at any given moment in time," so that they are more numerous than the stars.

As a Dispensationalist I was taught to fear Man rather than God! To hurry up and grab as many people as I could to sign up for the great "med-evac escape flight" before the big bad antichrist comes... my view of the kingdom at that time was that it was a desperate attempt by God to try and cut His losses, and that the kingdom depends as much on people as it did on the King. The kingdom is far away for now, but eventually destined to reconquer the earth - as a rebuilt Jewish-like theocracy.

Because eschatology defines the nature of the kingdom, it matters a great deal! And it has always disappointed me that the Reformed camp has been contect, for the most part, to treat it as "nonessential," allowing the completely unbiblical "Left Behind" scenario to become the majority report in the evangelical world.