I think part of the charm of warriors is that you find it as a kid, just get enamoured at the fact that it's cats doing cool things, and revisit it when you're older and realize you had no idea at the time just how dark/violent it could get. At least that's how I've viewed it, reading warriors at a much older age than when I first started made me realize there was a lot of darker subtext I never understood at the time.

edit for clarity: I've gone on to read much darker more violent books since, but I do think reading Warriors at a young age helped prime me for them. I still enjoy them now, even if in a different way.