Are the other eyes we have seen legitimate?

[Infant]

The Ketsuryugan and so on, particularly from the extra-canonical sources

Kakashi introduced the Byakugan as one of "the three great dojutsu".

This implies there are other eyes and eye-based powers out there, and that theyare decently well known.

With that in mind, should the eyes introduced in other sources be taken as legitimate and not the script writers' simply playing with concepts?

In light of that introduction from Kakashi, should canon sources have shown more eyes and eye-based powers in the story? Perhaps in organisations like Akatsuki and the Hidden Sound Village?

And what of the other senses? Should they have had special powered forms?

 

[Urda]

I wish more Eye powers (Doujutsu) were introduced in the Naruto Manga to rival the Uchiha Clan, but in all honesty, that ship has sailed. I don't think they would make it a good story in the Boruto series.

 

[Infant]

I don't think they would make it a good story in the Boruto series.

The problem with such long stories or successors to original stories is that what is built has to fit within what has already been laid as a foundation.

Otherwise the story is rendered ridiculous as the question can always be asked in terms of where the newer elements were when world threatening events were playing out.