I will say a few things in favor of discord despite my vote for teamspeak: Discord would be a better fit for a growing community of all kinds of people. Discord is more like a chat room with many sub channels of different purposes, and voice is not the main purpose of the application. That can be more appealing to those who do not have a proper microphone setup or just choose not to use it. Discord could also be used for announcements on events, starting groups for games, general discussion, and more. Take a look at how Your Overwatch has their channels set up:
Looks about right for a gaming community, eh?