I think eye size is important. Most spiders aren't considered cute but jumping spiders are an exception for many people because they have big eyes, e.g.:

https://en.wikipedia.org/wiki/Jumping_spider#/media/File:Pla...

And even the tachikoma from Ghost in the Shell: Stand Alone Complex (robots inspired by jumping spiders) can be considered cute:

https://en.wikipedia.org/wiki/Tachikoma