For reference, here is an older post of the same question where RRG explain that technically you can't have more than one, but they think it's cool if you do it anyway:
viewtopic.php?f=4&t=34553I still think it's an interesting question because it hits into one of the cores of the game's design philosophy, I think. That every model is a character is a very strong concept. But as the game expands, it doesn't have to be like this forever.
RRG could, for example, release a model at some point in the future that *isn't* a unique character. I'm not sure what it might be, but... let's imagine some kind of fighter that has a special rule saying "you may take more than one of this gladiator in your cohort", combined with another special rule where having more than one of them gives a bonus.
Personally, if people have a desire for generic beasts, then I would prefer for RRG to release rules and models for actual generic beasts, rather than making the character beasts generic as a house rule. For example, they could release a generic "giant scorpion" that would be similar to Sereqet, but on a 50mm base and slightly smaller. Maybe make them weaker, but say that one character slot used gives you two scorpions. That way you could retain Sereqet as the unique scorpion queen, as she was intended, but also introduce the concept of a swarm of generic scorpions for her to lead.