Cannon material Uzumaki/Senju clans would've be better then wanking one clan the entire series, made it stale. Just more background in general to most or all characters that where introduced..
Kishi created an entire verse an stayed in one corner of the verse instead of exploring... It suck the new gen is out honestly because there's to many unanswered questions an holes that leaves the fans to fill in the blanks (It's called fanfacts) cause Kishi didn't bother to go that far....