Beads, testing a person's work by fire has nothing to do with pruning unproductive branches from the vine. We are saved unto good works we are not saved by good works.
The author of Hebrews may have expected better things of his audience but that does not contradict that the author of Hebrews also states that a men can taste the Holy Spirit and then turn away. And when this happens the apostate cannot be saved again.
The Biblical definition of "church" is not an organization; the Biblical definition of "church" is the body of believers. Applying the word "church" to an organization or building developed after men started trying to control other men through doctrine.