Bump node can connect normal and roughness of color shader to change specular.
it doesn’t need to connect displace in material output. So bump nodes can be mixed, for example, by converter > vector math > cross product.
The three test materials below are subjected to bumped texture.
Texture nodes can be mixed as well. You can make links texture’s color to texture’s vector for hierarchical mixing.
The texture can distribute color along with the pattern by connecting fac of Mix RGB.
The three images below are the result of mixing texture.