There are definitely a lot of things missing from Clans in Destiny but that's probably because Destiny is an FPS game first, and MMORPG second (or third...fourth?). Extensive clan features like you'd see in WoW or other big MMOs just aren't the priority in Destiny for Bungie, or even its players. As much as I'd love to see more features implemented, even BASIC stuff like better control of Clan Admin roles, sticky messages in the clan chat channels, ability to broadcast a clan message to players in-game, etc...I don't think it'll happen. As for activity tracking, there are several platforms out there you can use to monitor this. Personally, I just use DestinyTracker.com. I open my clan up in that, go down the member list, opening up a tab of every player and quickly check who has been active recently. If they haven't been active in a long time, then I have another window with Bungie.net open and I kick them. I know in the era of phones, people want a better solution to do this on that platform but...doing it from a computer takes little time at all.