TotallyNotNyx

Yeah, they were. But they were applied to ponies themselves, instead of paper 

To this very day, I still wish that Rara returned in another episode.

She truly is my most favourite pony

I agree! With such a large cast of ponies, it's hard to give them all the spotlight they deserve, but there were some that definitely needed to appear more – Rara and Coco being obvious examples.

We did get to see human Rara (though she didn't get a speaking role, unfortunately)!

While I do agree that its difficult to giver everyone enough time in the spotlight, I do feel that the show focused way too much on mane 6. I think Hasbro was afraid that if they moved away from the Mane 6, the toy sales would drop.

And yeah, it was a nice touch to see her in human form, but it would have been so much better if she had had a role in one of the films or specials.