Keep the 70th, get the Kamado. You will not regret having the Kamado, ever, nor are you likely to regret having the kettle.
The Kamado is, simply put, just about the greatest cooker ever made. Is it expensive? Yeah. Is it heavy and not overly portable? Yeah. But the cooking is out of this world. Cold, windy conditions is what really separates it from a kettle for me, which is about 60-70% of the year here. It does everything a kettle does, but better.
The only reason the Summit Charcoal/Kamado cannot claim title as greatest cooker ever, is because the kettle has been around for 70 years and almost everyone has one or has at some point. Longevity and usability makes it head and shoulders above anything.