iEvent, Cohort, Blockland Classics are filled with nice, warm and friendly people, so you should join one of those, and no I'm not a shill haha. iEvent is a "clan based around social events", Cohort is more focused on building, and Blockland Classics is a good clan if you like filming as well as scripting and building sets. (Square Society is good too, it's pretty community based too, but you apparently don't meet the requirements)
Since you asked for productive clans, don't consider joining the "Blockland Olympiad Committee" or the "Blockland News Channel" as they don't seem to be too productive or long lasting. Glad I could help :)
