Unless specific mechanics call for everyone to be way apart from each other, everyone should be close enough for you to hit them at 7y anyway.
Other AoEs people miss out on if they're out in left field:
Celestial Opposition - 10y
Deployment Tactics - 10y
Sacred Soil - 8y
Collective Unconscious - 6y
Asylum - 6y
Cure III - 6y
Incidentally, the set of use cases for these abilities has a large intersection with the set of use cases for Mantra (Mantra only actually affects one and a half of those, but still it would be used in the same situations as most of those).