I would suggest any of them but Jiko. We went to several signature experiences and all of them were fairly kid friendly (we always went early and saw quite a few other kids there) We went to Jiko at about the same time as our other ADR's, and the atmosphere is more adult and we didn't see any kids at all. Not that kids are not allowed at Jiko, they are allowed, it's just not what I'd suggest for a kid friendly signature dining experience.