Overall characteristics
Do the overall characteristics indicate that the piece is within the performance realm of your ensemble? Is it technically within the grasp of your singers? There are many fine pieces that technically lie outside the grasp of many choirs. The notes may be so difficult to learn that the choir will never be able to get beyond this initial stage with the piece.
Can your choir achieve the choral sonority necessary for a musical performance of the work? There are many works whose technical demands place them within the reach of high school singers, but whose artistic merits also warrant performances by college, university, and professional choirs. Although high school students will not have the richness of tone that maturity and advance training brings, they can have a musicality and precision that excellent performances anywhere will have.