1 hair is buggy enough why make it 2

Because if we bought two hair styles, we would want both to be activated.

mostly hats can be actiavated with beards such as a green hat/santa beard at the same time

Would cat Ears & Dread tail work together?

It depends if the hairs hit each other if they touch each other they can't go try something like dinamyo hat and scarf with santa beard

I've tried it with Santa beard and mohawk and it is not working

I think it has something to do with this:

Lets say Mohawk is 6 particles, dread tail is 4 particles, and the max particles you can have is 10. They work together because they don't go over 10.

Mohawk is 6 particles and jiyu dreads are 7 particles? Not gonna work, I think its something like that.

Here try santa hat and santa beard then