I'm sorry if this is a repeat but...
...what about Adoptable Stats? Say, for each different Class, their could be a min value and a max, like so:
Intelligents: [min] to [max]
Strength: [min] to [max]
Speed: [min] to [max]
Stamina: [min] to [max]
And then an adoptable of that class can end up with any value between the min and max of that stat, say:
Intelligents: [5] to [10]
And then an adopt in that class could end up with 5, 6, 7, 8, 9, or 10 for intelligents. Because, really, each different class of adoptable should have more of one thing and less of another, like a cheetah would have high speed, but low stamina...so adoptables would have more variation, and there'd be greater differences between classes...
I have no idea if that all makes sense, I can try to explain it better, if need be...
Thanks,
Iris