Id record everything in 4K now. That way when I have a 4K TV I can watch all my memories in glorious 4K action.
I respect that choice, but have to wonder how much 4K video you're going to be able to capture at once. My camera will shoot 720p for close to half an hour at a time. If I shoot at 1080p I only get a few minutes and then have to press (record) again to restart recording. When I'm trying to capture an event I typically leave it set to 720 so I don't miss anything.