Seems like a bit of a disservice to how Jimmy's has reached this point - his minor celebrity fame came from his rare breeds farm becoming a major success, which is where the vast majority of the original park income came from. I would imagine there was a point in the past few years where the Zoo income became greater than the rare breeds, but regardless - I would say the majority of Jimmy's success has come from pacing themselves over the past decade, making the most of their natural landscape, and prioritising the animals with the exhibits moreso than visitor experience (which of course then sustains a better visitor experience anyway). I think it also helps that he has a tremendous amount of local goodwill and have mastered the art of the animal "rescue" (although arguably their acquisitions of that sort have been more rescue than most other collections)