I kinda have an issue with the seemingly very limited number of characters they can draw.

Eh, that's true of a lot of creators. A lot of Hakamada Mera's characters look similar, and Shimura Takako makes fun of her own tendency for sameface. Personally, I don't mind so much if the story's good.

Personally: I like it. When i like those characters then i don't have to get used to new faces and stuff, i know, it's kinda hard to tell if she's someone different or the same person but nm. And i would say that's the nice thing - Every artist has their own way of drawing stuff so it's interesting. + Bonus - you can try to guess the artist by their drawing instead of lookin' who drew it. If you guess it right, you can feel good about yourself xD

This author really gives some angsty stories ;_;

I really love this author.