I really really second this feature. My only issue with the bot (as well as everyone in my channel) is the fact that users sometimes go 'idle' and it's taken as a reconnect so the next time they talk they are welcomed again. Sometimes that time frame is QUITE short (minutes)... and sometimes the bot just flips out and greets people like crazy for no reason. People like to say the bot is drunk/crazy. I've almost debated turning welcomes off entirely because of this. (And mine are set to welcome on first chat, not entry to the channel). It get's spammy sometimes. =/
Welcome Backs/ Custom Welcomes REALLY need a cooldown setting. Depending on how long my stream that day is I'd love to be able to set it to 3-4 hours between people being able to be welcomed again. That way we could really cut down on spam and a user will only be welcomed once or twice a day with a good chunk of time in-between.