It’s a common observation that a lot of new music for churches is not recorded in keys best suited to congregational singing. This can also be true of older settings for hymns.
As I search around for hints about finding suitable keys for newer songs this article by Luke Woodard at a site called Discover Worship offers helpful guidance while not being prescriptive.
It makes observations about finding a useful key (usually lower) but offers considerations to take into account so as best preserve the tone of the song as well.
Read The Wrong Key at Discover Worship.
mgpcpastor's blog 
This is such an awkward area. You want to give the musicians a hint that they are torturing your vocal chords with impossibly high music but you don’t want to hurt their feelings when they are so kind in practising and playing each week. But, folks, just because you can play it, doesn’t mean we can sing it.
It helps that I pretty much source the sheet music for new songs. The song select thing with transposable sheet music options is magic. The key thing with contemporary songs seems to have become more of a thing over the last fifteen or so years. Male vocalists seem to be high, females – oddly enough – are low. Some publishing places even have ‘recorded key’ / ‘congregational key’ options.