Not all procedurals will convert to texture maps perfectly since they're mathematically based - there is a reason that texture painting is worth while ;-) . I haven't tried Baker so I can't tell you if that solution is a better option than Carrara's native export. 

If you take time  to name the shading domains, those texture names should export automatically - at least they do on my rig.

The naming issue is really (believe it or not) a good thing for yourself or other users of the model once opened in .obj format. If the texture names are all the same, except for a number, tracking down and changing a texture can be a huge pain for the user. On a couple of assignments where I needed to use purchased models, I could  have killed the author because the textures we only numbers so tracking them down and  modifying them was a time  killer.  

So, if you're going to be selling your creations, the easier you can make it on your customers will pay of in continued sales. ;-)