I did look at Discord pretty hard and even set it all up for this community. But in the end I decided that enough of my existing network, friends, etc. have Slack on their devices to keep it simple to begin. Also, there's just enough of a download/learning gap that I didn't want to risk. It appears that if we want we could transition to Discord later, but I don't have any experience doing that. Have you seen people get stuck on the wrong tool and be unable to transition?