It's been said a few times but will totes also agree with it...
Required voice chat.
I was in a guild a while back where a majority of the 'core' group were in TS almost all the time. Which was fine, they were having fun and that's what mattered! What was NOT fine was how they'd disregard FC chat and their other channels that a number of the other members preferred to use. They'd miss when people would ask for help with runs, general questions, ask for RP, etc. It drove a number of people away and especially in the last few years it's been one of the more common complaints I've heard about with guilds.
Required voice chat.
I was in a guild a while back where a majority of the 'core' group were in TS almost all the time. Which was fine, they were having fun and that's what mattered! What was NOT fine was how they'd disregard FC chat and their other channels that a number of the other members preferred to use. They'd miss when people would ask for help with runs, general questions, ask for RP, etc. It drove a number of people away and especially in the last few years it's been one of the more common complaints I've heard about with guilds.