If you like Purrli, I'm sure that you will love his https://mynoise.net/ which is the ultimate noise generator out there. It allows you to choose from a huge repertoire of customizable soundscapes. There's a cat noise generator, but there's also rain, fire, plane noises, Japanese gardens, didgeridoo, sled dogs, spaceship engines, etc.
There's even a subreddit where people mix up some of the soundscapes together to create amazing results: https://www.reddit.com/r/MyNoise/
I use his websites daily, couldn't work without some quality background noise. You can set the soundscape to "animate" and your ears won't get tired of the sound.
If the complexity of myNoise puts you off, try some of his other sites that are more similar to purrly: https://rain.today/ https://brainaural.com/ https://calmyleon.com/ https://noises.online/